kc3-lang/libffi

diff --git a/.circleci/config.yml b/.circleci/config.yml
new file mode 100644
index 0000000..aaf6556
--- /dev/null
+++ b/.circleci/config.yml
@@ -0,0 +1,157 @@
+version: 2.1
+
+defaults: &defaults
+  working_directory: ~/repo
+  docker:
+    # Built from:
+    # https://github.com/pyodide/pyodide/blob/2ab4b0ab6aefe99fd994bb4f9ab086e5c0aebb7b/Dockerfile
+    - image: pyodide/pyodide-env:20230126-chrome109-firefox109-py311
+
+jobs:
+  install-emsdk:
+    <<: *defaults
+    steps:
+      - checkout
+      - run:
+          name: install emsdk
+          command: |
+            git clone https://github.com/emscripten-core/emsdk.git --depth=1
+            cd emsdk
+            ./emsdk install 3.1.30
+            ./emsdk activate 3.1.30
+
+      - persist_to_workspace:
+          root: .
+          paths:
+            - emsdk
+
+  build:
+    parameters:
+      wasm-bigint:
+        description: Should we build with wasm-bigint?
+        type: string
+        default: ""
+    environment:
+      WASM_BIGINT: << parameters.wasm-bigint >>
+    <<: *defaults
+    steps:
+      - checkout
+      - attach_workspace:
+          at: .
+
+      - run:
+          name: build
+          command: |
+            source ./emsdk/emsdk_env.sh
+            ./testsuite/emscripten/build.sh
+
+      - run:
+          name: build tests
+          command: |
+            source ./emsdk/emsdk_env.sh
+            cp -r testsuite/libffi.call testsuite/libffi.call.test
+            cp -r testsuite/libffi.closures testsuite/libffi.closures.test
+            ./testsuite/emscripten/build-tests.sh testsuite/libffi.call.test
+            ./testsuite/emscripten/build-tests.sh testsuite/libffi.closures.test
+
+      - persist_to_workspace:
+          root: .
+          paths:
+            - target
+            - testsuite
+
+  test:
+    parameters:
+      test-params:
+        description: The tests to run.
+        type: string
+    <<: *defaults
+    steps:
+      - checkout
+
+      - attach_workspace:
+          at: .
+
+      - run:
+          name: run tests
+          command: |
+            git reset --hard
+            cd testsuite/emscripten/
+            mkdir test-results
+            pytest \
+              --junitxml=test-results/junit.xml \
+               test_libffi.py \
+               << parameters.test-params >>
+      - store_test_results:
+          path: testsuite/emscripten/test-results
+
+  test-dejagnu:
+    parameters:
+      params:
+        description: Parameters to node-tests
+        type: string
+        default: ""
+
+    <<: *defaults
+    steps:
+      - checkout
+
+      - attach_workspace:
+          at: .
+
+      - run:
+          name: run tests
+          command: |
+            source ./emsdk/emsdk_env.sh
+            python3 testsuite/emscripten/quiet_emcc_info.py
+            testsuite/emscripten/node-tests.sh << parameters.params >>
+
+workflows:
+  version: 2
+  build-and-test:
+    jobs:
+      - install-emsdk
+
+      - build:
+          name: build
+          requires:
+            - install-emsdk
+
+      - build:
+          name: build-bigint
+          wasm-bigint: "true"
+          requires:
+            - install-emsdk
+
+      - test:
+          name: test-firefox
+          test-params: -k firefox
+          requires:
+            - build
+      - test:
+          name: test-chrome
+          test-params: -k chrome
+          requires:
+            - build
+
+      - test:
+          name: test-firefox-bigint
+          test-params: -k firefox
+          requires:
+            - build-bigint
+
+      - test:
+          name: test-chrome-bigint
+          test-params: -k chrome
+          requires:
+            - build-bigint
+
+      - test-dejagnu:
+          name: test-dejagnu
+          requires:
+            - install-emsdk
+      - test-dejagnu:
+          name: test-dejagnu-bigint
+          params: --enable-wasm-bigint
+          requires:
+            - install-emsdk
diff --git a/.gitignore b/.gitignore
index f33ca3d..dea0b1b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,10 @@
 .deps
 *.o
 *.lo
+*.wasm
+*.js
+*.test
+*.log
 .dirstamp
 *.la
 Makefile
@@ -35,3 +39,8 @@ build_*/
 darwin_*/
 src/arm/trampoline.S
 **/texinfo.tex
+target/
+__pycache__
+.docker_home
+emsdk
+test-results
diff --git a/Makefile.am b/Makefile.am
index fde7ec2..3de0bea 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -62,6 +62,7 @@ noinst_HEADERS = src/aarch64/ffitarget.h src/aarch64/internal.h		\
 	src/s390/ffitarget.h src/s390/internal.h src/sh/ffitarget.h	\
 	src/sh64/ffitarget.h src/sparc/ffitarget.h			\
 	src/sparc/internal.h src/tile/ffitarget.h src/vax/ffitarget.h	\
+	src/wasm32/ffitarget.h \
 	src/x86/ffitarget.h src/x86/internal.h src/x86/internal64.h	\
 	src/x86/asmnames.h src/xtensa/ffitarget.h src/dlmalloc.c	\
 	src/kvx/ffitarget.h src/kvx/asm.h				\
@@ -92,6 +93,7 @@ EXTRA_libffi_la_SOURCES = src/aarch64/ffi.c src/aarch64/sysv.S		\
 	src/sh64/sysv.S src/sparc/ffi.c src/sparc/ffi64.c		\
 	src/sparc/v8.S src/sparc/v9.S src/tile/ffi.c src/tile/tile.S	\
 	src/vax/ffi.c src/vax/elfbsd.S src/x86/ffi.c src/x86/sysv.S	\
+	src/wasm32/ffi.c \
 	src/x86/ffiw64.c src/x86/win64.S src/x86/ffi64.c		\
 	src/x86/unix64.S src/x86/sysv_intel.S src/x86/win64_intel.S	\
 	src/xtensa/ffi.c src/xtensa/sysv.S src/kvx/ffi.c		\
diff --git a/configure.host b/configure.host
index a4ca511..b291bd0 100644
--- a/configure.host
+++ b/configure.host
@@ -265,6 +265,11 @@ case "${host}" in
 	SOURCES="ffi.c elfbsd.S"
 	;;
 
+  wasm32-*-*)
+	TARGET=wasm32; TARGETDIR=wasm32
+	SOURCES="ffi.c"
+	;;
+
   xtensa*-*)
 	TARGET=XTENSA; TARGETDIR=xtensa
 	SOURCES="ffi.c sysv.S"
diff --git a/src/closures.c b/src/closures.c
index 5c43313..0f2d619 100644
--- a/src/closures.c
+++ b/src/closures.c
@@ -31,6 +31,8 @@
 #define _GNU_SOURCE 1
 #endif
 
+#ifndef __EMSCRIPTEN__
+
 #include <fficonfig.h>
 #include <ffi.h>
 #include <ffi_common.h>
@@ -1102,3 +1104,4 @@ ffi_tramp_is_present (__attribute__((unused)) void *ptr)
 #endif /* FFI_CLOSURES */
 
 #endif /* NetBSD with PROT_MPROTECT */
+#endif /* __EMSCRIPTEN__ */
diff --git a/src/wasm32/ffi.c b/src/wasm32/ffi.c
new file mode 100644
index 0000000..399a06e
--- /dev/null
+++ b/src/wasm32/ffi.c
@@ -0,0 +1,934 @@
+/* -----------------------------------------------------------------------
+   ffi.c - Copyright (c) 2018-2023  Hood Chatham, Brion Vibber, Kleis Auke Wolthuizen, and others.
+
+   wasm32/emscripten Foreign Function Interface
+
+   Permission is hereby granted, free of charge, to any person obtaining
+   a copy of this software and associated documentation files (the
+   ``Software''), to deal in the Software without restriction, including
+   without limitation the rights to use, copy, modify, merge, publish,
+   distribute, sublicense, and/or sell copies of the Software, and to
+   permit persons to whom the Software is furnished to do so, subject to
+   the following conditions:
+
+   The above copyright notice and this permission notice shall be included
+   in all copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
+   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+   NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+   DEALINGS IN THE SOFTWARE.
+   ----------------------------------------------------------------------- */
+
+#include <ffi.h>
+#include <ffi_common.h>
+
+#include <stdlib.h>
+#include <stdint.h>
+
+#include <emscripten/emscripten.h>
+
+#ifdef DEBUG_F
+#define LOG_DEBUG(args...)  \
+  console.warn(`====LIBFFI(line __LINE__)`, args)
+#else
+#define LOG_DEBUG(args...) 0
+#endif
+
+#define EM_JS_MACROS(ret, name, args, body...) EM_JS(ret, name, args, body)
+
+#if WASM_BIGINT
+EM_JS_DEPS(libffi, "$getWasmTableEntry,$setWasmTableEntry,$getEmptyTableSlot,$convertJsFunctionToWasm");
+#define CALL_FUNCTION_POINTER(ptr, args...) \
+  (LOG_DEBUG("CALL_FUNC_PTR", ptr, args),   \
+  getWasmTableEntry(ptr).apply(null, args))
+
+#define JS_FUNCTION_TO_WASM convertJsFunctionToWasm
+#else
+EM_JS_DEPS(libffi, "$getWasmTableEntry,$setWasmTableEntry,$getEmptyTableSlot,$convertJsFunctionToWasm,$dynCall,$generateFuncType,$uleb128Encode");
+#define CALL_FUNCTION_POINTER(ptr, args...)     \
+  (LOG_DEBUG("CALL_FUNC_PTR", sig, ptr, args),  \
+  dynCall(sig, ptr, args))
+
+#define JS_FUNCTION_TO_WASM createLegalizerWrapper
+#endif
+
+// Signature calculations are not needed if WASM_BIGINT is present.
+#if WASM_BIGINT
+#define SIG(sig)
+#else
+#define SIG(sig) sig
+#endif
+
+#define DEREF_U8(addr, offset) HEAPU8[addr + offset]
+#define DEREF_S8(addr, offset) HEAP8[addr + offset]
+#define DEREF_U16(addr, offset) HEAPU16[(addr >> 1) + offset]
+#define DEREF_S16(addr, offset) HEAP16[(addr >> 1) + offset]
+#define DEREF_U32(addr, offset) HEAPU32[(addr >> 2) + offset]
+#define DEREF_S32(addr, offset) HEAP32[(addr >> 2) + offset]
+
+#define DEREF_F32(addr, offset) HEAPF32[(addr >> 2) + offset]
+#define DEREF_F64(addr, offset) HEAPF64[(addr >> 3) + offset]
+
+#if WASM_BIGINT
+// We have HEAPU64 in this case.
+#define DEREF_U64(addr, offset) HEAPU64[(addr >> 3) + offset]
+#endif
+
+
+#define CHECK_FIELD_OFFSET(struct, field, offset)                                  \
+  _Static_assert(                                                                  \
+    offsetof(struct, field) == offset,                                             \
+    "Memory layout of '" #struct "' has changed: '" #field "' is in an unexpected location");
+
+CHECK_FIELD_OFFSET(ffi_cif, abi, 4*0);
+CHECK_FIELD_OFFSET(ffi_cif, nargs, 4*1);
+CHECK_FIELD_OFFSET(ffi_cif, arg_types, 4*2);
+CHECK_FIELD_OFFSET(ffi_cif, rtype, 4*3);
+CHECK_FIELD_OFFSET(ffi_cif, nfixedargs, 4*6);
+
+#define CIF__ABI(addr) DEREF_U32(addr, 0)
+#define CIF__NARGS(addr) DEREF_U32(addr, 1)
+#define CIF__ARGTYPES(addr) DEREF_U32(addr, 2)
+#define CIF__RTYPE(addr) DEREF_U32(addr, 3)
+#define CIF__NFIXEDARGS(addr) DEREF_U32(addr, 6)
+
+CHECK_FIELD_OFFSET(ffi_type, size, 0);
+CHECK_FIELD_OFFSET(ffi_type, alignment, 4);
+CHECK_FIELD_OFFSET(ffi_type, type, 6);
+CHECK_FIELD_OFFSET(ffi_type, elements, 8);
+
+#define FFI_TYPE__SIZE(addr) DEREF_U32(addr, 0)
+#define FFI_TYPE__ALIGN(addr) DEREF_U16(addr + 4, 0)
+#define FFI_TYPE__TYPEID(addr) DEREF_U16(addr + 6, 0)
+#define FFI_TYPE__ELEMENTS(addr) DEREF_U32(addr + 8, 0)
+
+#define ALIGN_ADDRESS(addr, align) (addr &= (~((align) - 1)))
+#define STACK_ALLOC(stack, size, align) ((stack -= (size)), ALIGN_ADDRESS(stack, align))
+
+// Most wasm runtimes support at most 1000 Js trampoline args.
+#define MAX_ARGS 1000
+
+#include <stddef.h>
+
+#define VARARGS_FLAG 1
+
+#define FFI_OK_MACRO 0
+_Static_assert(FFI_OK_MACRO == FFI_OK, "FFI_OK must be 0");
+
+#define FFI_BAD_TYPEDEF_MACRO 1
+_Static_assert(FFI_BAD_TYPEDEF_MACRO == FFI_BAD_TYPEDEF, "FFI_BAD_TYPEDEF must be 1");
+
+ffi_status FFI_HIDDEN
+ffi_prep_cif_machdep(ffi_cif *cif)
+{
+  if (cif->abi != FFI_WASM32_EMSCRIPTEN)
+    return FFI_BAD_ABI;
+  // This is called after ffi_prep_cif_machdep_var so we need to avoid
+  // overwriting cif->nfixedargs.
+  if (!(cif->flags & VARARGS_FLAG))
+    cif->nfixedargs = cif->nargs;
+  if (cif->nargs > MAX_ARGS)
+    return FFI_BAD_TYPEDEF;
+  if (cif->rtype->type == FFI_TYPE_COMPLEX)
+    return FFI_BAD_TYPEDEF;
+  // If they put the COMPLEX type into a struct we won't notice, but whatever.
+  for (int i = 0; i < cif->nargs; i++)
+    if (cif->arg_types[i]->type == FFI_TYPE_COMPLEX)
+      return FFI_BAD_TYPEDEF;
+  return FFI_OK;
+}
+
+ffi_status FFI_HIDDEN
+ffi_prep_cif_machdep_var(ffi_cif *cif, unsigned nfixedargs, unsigned ntotalargs)
+{
+  cif->flags |= VARARGS_FLAG;
+  cif->nfixedargs = nfixedargs;
+  // The varargs takes up one extra argument
+  if (cif->nfixedargs + 1 > MAX_ARGS)
+    return FFI_BAD_TYPEDEF;
+  return FFI_OK;
+}
+
+/**
+ * A Javascript helper function. This takes an argument typ which is a wasm
+ * pointer to an ffi_type object. It returns a pair a type and a type id.
+ *
+ *    - If it is not a struct, return its type and its typeid field.
+ *    - If it is a struct of size >= 2, return the type and its typeid (which
+ *      will be FFI_TYPE_STRUCT)
+ *    - If it is a struct of size 0, return FFI_TYPE_VOID (????? this is broken)
+ *    - If it is a struct of size 1, replace it with the single field and apply
+ *      the same logic again to that.
+ *
+ * By always unboxing structs up front, we can avoid messy casework later.
+ */
+EM_JS_MACROS(
+void,
+unbox_small_structs, (ffi_type type_ptr), {
+  var type_id = FFI_TYPE__TYPEID(type_ptr);
+  while (type_id === FFI_TYPE_STRUCT) {
+    var elements = FFI_TYPE__ELEMENTS(type_ptr);
+    var first_element = DEREF_U32(elements, 0);
+    if (first_element === 0) {
+      type_id = FFI_TYPE_VOID;
+      break;
+    } else if (DEREF_U32(elements, 1) === 0) {
+      type_ptr = first_element;
+      type_id = FFI_TYPE__TYPEID(first_element);
+    } else {
+      break;
+    }
+  }
+  return [type_ptr, type_id];
+})
+
+EM_JS_MACROS(
+void,
+ffi_call_js, (ffi_cif *cif, ffi_fp fn, void *rvalue, void **avalue),
+{
+  var abi = CIF__ABI(cif);
+  var nargs = CIF__NARGS(cif);
+  var nfixedargs = CIF__NFIXEDARGS(cif);
+  var arg_types_ptr = CIF__ARGTYPES(cif);
+  var rtype_unboxed = unbox_small_structs(CIF__RTYPE(cif));
+  var rtype_ptr = rtype_unboxed[0];
+  var rtype_id = rtype_unboxed[1];
+  var orig_stack_ptr = stackSave();
+  var cur_stack_ptr = orig_stack_ptr;
+
+  var args = [];
+  // Does our onwards call return by argument or normally? We return by argument
+  // no matter what.
+  var ret_by_arg = false;
+
+  if (rtype_id === FFI_TYPE_COMPLEX) {
+    throw new Error('complex ret marshalling nyi');
+  }
+  if (rtype_id < 0 || rtype_id > FFI_TYPE_LAST) {
+    throw new Error('Unexpected rtype ' + rtype_id);
+  }
+  // If the return type is a struct with multiple entries or a long double, the
+  // function takes an extra first argument which is a pointer to return value.
+  // Conveniently, we've already received a pointer to return value, so we can
+  // just use this. We also mark a flag that we don't need to convert the return
+  // value of the dynamic call back to C.
+  if (rtype_id === FFI_TYPE_LONGDOUBLE || rtype_id === FFI_TYPE_STRUCT) {
+    args.push(rvalue);
+    ret_by_arg = true;
+  }
+
+  SIG(var sig = "");
+
+#if !WASM_BIGINT
+  switch(rtype_id) {
+  case FFI_TYPE_VOID:
+    SIG(sig = 'v');
+    break;
+  case FFI_TYPE_STRUCT:
+  case FFI_TYPE_LONGDOUBLE:
+    SIG(sig = 'vi');
+    break;
+  case FFI_TYPE_INT:
+  case FFI_TYPE_UINT8:
+  case FFI_TYPE_SINT8:
+  case FFI_TYPE_UINT16:
+  case FFI_TYPE_SINT16:
+  case FFI_TYPE_UINT32:
+  case FFI_TYPE_SINT32:
+  case FFI_TYPE_POINTER:
+    SIG(sig = 'i');
+    break;
+  case FFI_TYPE_FLOAT:
+    SIG(sig = 'f');
+    break;
+  case FFI_TYPE_DOUBLE:
+    SIG(sig = 'd');
+    break;
+  case FFI_TYPE_UINT64:
+  case FFI_TYPE_SINT64:
+    SIG(sig = 'j');
+    break;
+  }
+#endif
+
+  // Accumulate a Javascript list of arguments for the Javascript wrapper for
+  // the wasm function. The Javascript wrapper does a type conversion from
+  // Javascript to C automatically, here we manually do the inverse conversion
+  // from C to Javascript.
+  for (var i = 0; i < nfixedargs; i++) {
+    var arg_ptr = DEREF_U32(avalue, i);
+    var arg_unboxed = unbox_small_structs(DEREF_U32(arg_types_ptr, i));
+    var arg_type_ptr = arg_unboxed[0];
+    var arg_type_id = arg_unboxed[1];
+
+    // It's okay here to always use unsigned integers as long as the size is 32
+    // or 64 bits. Smaller sizes get extended to 32 bits differently according
+    // to whether they are signed or unsigned.
+    switch (arg_type_id) {
+    case FFI_TYPE_INT:
+    case FFI_TYPE_SINT32:
+    case FFI_TYPE_UINT32:
+    case FFI_TYPE_POINTER:
+      args.push(DEREF_U32(arg_ptr, 0));
+      SIG(sig += 'i');
+      break;
+    case FFI_TYPE_FLOAT:
+      args.push(DEREF_F32(arg_ptr, 0));
+      SIG(sig += 'f');
+      break;
+    case FFI_TYPE_DOUBLE:
+      args.push(DEREF_F64(arg_ptr, 0));
+      SIG(sig += 'd');
+      break;
+    case FFI_TYPE_UINT8:
+      args.push(DEREF_U8(arg_ptr, 0));
+      SIG(sig += 'i');
+      break;
+    case FFI_TYPE_SINT8:
+      args.push(DEREF_S8(arg_ptr, 0));
+      SIG(sig += 'i');
+      break;
+    case FFI_TYPE_UINT16:
+      args.push(DEREF_U16(arg_ptr, 0));
+      SIG(sig += 'i');
+      break;
+    case FFI_TYPE_SINT16:
+      args.push(DEREF_S16(arg_ptr, 0));
+      SIG(sig += 'i');
+      break;
+    case FFI_TYPE_UINT64:
+    case FFI_TYPE_SINT64:
+      #if WASM_BIGINT
+      args.push(DEREF_U64(arg_ptr, 0));
+      #else
+      args.push(DEREF_U32(arg_ptr, 0));
+      args.push(DEREF_U32(arg_ptr, 1));
+      #endif
+      SIG(sig += 'j');
+      break;
+    case FFI_TYPE_LONGDOUBLE:
+      // long double is passed as a pair of BigInts.
+      #if WASM_BIGINT
+      args.push(DEREF_U64(arg_ptr, 0));
+      args.push(DEREF_U64(arg_ptr, 1));
+      #else
+      args.push(DEREF_U32(arg_ptr, 0));
+      args.push(DEREF_U32(arg_ptr, 1));
+      args.push(DEREF_U32(arg_ptr, 2));
+      args.push(DEREF_U32(arg_ptr, 3));
+      #endif
+      SIG(sig += "jj");
+      break;
+    case FFI_TYPE_STRUCT:
+      // Nontrivial structs are passed by pointer.
+      // Have to copy the struct onto the stack though because C ABI says it's
+      // call by value.
+      var size = FFI_TYPE__SIZE(arg_type_ptr);
+      var align = FFI_TYPE__ALIGN(arg_type_ptr);
+      STACK_ALLOC(cur_stack_ptr, size, align);
+      HEAP8.subarray(cur_stack_ptr, cur_stack_ptr+size).set(HEAP8.subarray(arg_ptr, arg_ptr + size));
+      args.push(cur_stack_ptr);
+      SIG(sig += 'i');
+      break;
+    case FFI_TYPE_COMPLEX:
+      throw new Error('complex marshalling nyi');
+    default:
+      throw new Error('Unexpected type ' + arg_type_id);
+    }
+  }
+
+  // Wasm functions can't directly manipulate the callstack, so varargs
+  // arguments have to go on a separate stack. A varags function takes one extra
+  // argument which is a pointer to where on the separate stack the args are
+  // located. Because stacks are allocated backwards, we have to loop over the
+  // varargs backwards.
+  //
+  // We don't have any way of knowing how many args were actually passed, so we
+  // just always copy extra nonsense past the end. The ownwards call will know
+  // not to look at it.
+  if (nfixedargs != nargs) {
+    SIG(sig += 'i');
+    var struct_arg_info = [];
+    for (var i = nargs - 1;  i >= nfixedargs; i--) {
+      var arg_ptr = DEREF_U32(avalue, i);
+      var arg_unboxed = unbox_small_structs(DEREF_U32(arg_types_ptr, i));
+      var arg_type_ptr = arg_unboxed[0];
+      var arg_type_id = arg_unboxed[1];
+      switch (arg_type_id) {
+      case FFI_TYPE_UINT8:
+      case FFI_TYPE_SINT8:
+        STACK_ALLOC(cur_stack_ptr, 1, 1);
+        DEREF_U8(cur_stack_ptr, 0) = DEREF_U8(arg_ptr, 0);
+        break;
+      case FFI_TYPE_UINT16:
+      case FFI_TYPE_SINT16:
+        STACK_ALLOC(cur_stack_ptr, 2, 2);
+        DEREF_U16(cur_stack_ptr, 0) = DEREF_U16(arg_ptr, 0);
+        break;
+      case FFI_TYPE_INT:
+      case FFI_TYPE_UINT32:
+      case FFI_TYPE_SINT32:
+      case FFI_TYPE_POINTER:
+      case FFI_TYPE_FLOAT:
+        STACK_ALLOC(cur_stack_ptr, 4, 4);
+        DEREF_U32(cur_stack_ptr, 0) = DEREF_U32(arg_ptr, 0);
+        break;
+      case FFI_TYPE_DOUBLE:
+      case FFI_TYPE_UINT64:
+      case FFI_TYPE_SINT64:
+        STACK_ALLOC(cur_stack_ptr, 8, 8);
+        DEREF_U32(cur_stack_ptr, 0) = DEREF_U32(arg_ptr, 0);
+        DEREF_U32(cur_stack_ptr, 1) = DEREF_U32(arg_ptr, 1);
+        break;
+      case FFI_TYPE_LONGDOUBLE:
+        STACK_ALLOC(cur_stack_ptr, 16, 8);
+        DEREF_U32(cur_stack_ptr, 0) = DEREF_U32(arg_ptr, 0);
+        DEREF_U32(cur_stack_ptr, 1) = DEREF_U32(arg_ptr, 1);
+        DEREF_U32(cur_stack_ptr, 2) = DEREF_U32(arg_ptr, 2);
+        DEREF_U32(cur_stack_ptr, 3) = DEREF_U32(arg_ptr, 3);
+        break;
+      case FFI_TYPE_STRUCT:
+        // Again, struct must be passed by pointer.
+        // But ABI is by value, so have to copy struct onto stack.
+        // Currently arguments are going onto stack so we can't put it there now. Come back for this.
+        STACK_ALLOC(cur_stack_ptr, 4, 4);
+        struct_arg_info.push([cur_stack_ptr, arg_ptr, FFI_TYPE__SIZE(arg_type_ptr), FFI_TYPE__ALIGN(arg_type_ptr)]);
+        break;
+      case FFI_TYPE_COMPLEX:
+        throw new Error('complex arg marshalling nyi');
+      default:
+        throw new Error('Unexpected argtype ' + arg_type_id);
+      }
+    }
+    // extra normal argument which is the pointer to the varargs.
+    args.push(cur_stack_ptr);
+    // Now allocate variable struct args on stack too.
+    for (var i = 0; i < struct_arg_info.length; i++) {
+      var struct_info = struct_arg_info[i];
+      var arg_target = struct_info[0];
+      var arg_ptr = struct_info[1];
+      var size = struct_info[2];
+      var align = struct_info[3];
+      STACK_ALLOC(cur_stack_ptr, size, align);
+      HEAP8.subarray(cur_stack_ptr, cur_stack_ptr+size).set(HEAP8.subarray(arg_ptr, arg_ptr + size));
+      DEREF_U32(arg_target, 0) = cur_stack_ptr;
+    }
+  }
+  stackRestore(cur_stack_ptr);
+  stackAlloc(0); // stackAlloc enforces alignment invariants on the stack pointer
+  var result = CALL_FUNCTION_POINTER(fn, args);
+  // Put the stack pointer back (we moved it if there were any struct args or we
+  // made a varargs call)
+  stackRestore(orig_stack_ptr);
+
+  // We need to return by argument. If return value was a nontrivial struct or
+  // long double, the onwards call already put the return value in rvalue
+  if (ret_by_arg) {
+    return;
+  }
+
+  // Otherwise the result was automatically converted from C into Javascript and
+  // we need to manually convert it back to C.
+  switch (rtype_id) {
+  case FFI_TYPE_VOID:
+    break;
+  case FFI_TYPE_INT:
+  case FFI_TYPE_UINT32:
+  case FFI_TYPE_SINT32:
+  case FFI_TYPE_POINTER:
+    DEREF_U32(rvalue, 0) = result;
+    break;
+  case FFI_TYPE_FLOAT:
+    DEREF_F32(rvalue, 0) = result;
+    break;
+  case FFI_TYPE_DOUBLE:
+    DEREF_F64(rvalue, 0) = result;
+    break;
+  case FFI_TYPE_UINT8:
+  case FFI_TYPE_SINT8:
+    DEREF_U8(rvalue, 0) = result;
+    break;
+  case FFI_TYPE_UINT16:
+  case FFI_TYPE_SINT16:
+    DEREF_U16(rvalue, 0) = result;
+    break;
+  case FFI_TYPE_UINT64:
+  case FFI_TYPE_SINT64:
+    #if WASM_BIGINT
+    DEREF_U64(rvalue, 0) = result;
+    #else
+    DEREF_U32(rvalue, 0) = result;
+    DEREF_U32(rvalue, 1) = getTempRet0();
+    #endif
+    break;
+  case FFI_TYPE_COMPLEX:
+    throw new Error('complex ret marshalling nyi');
+  default:
+    throw new Error('Unexpected rtype ' + rtype_id);
+  }
+});
+
+void ffi_call(ffi_cif *cif, void (*fn)(void), void *rvalue, void **avalue) {
+  ffi_call_js(cif, fn, rvalue, avalue);
+}
+
+CHECK_FIELD_OFFSET(ffi_closure, ftramp, 4*0);
+CHECK_FIELD_OFFSET(ffi_closure, cif, 4*1);
+CHECK_FIELD_OFFSET(ffi_closure, fun, 4*2);
+CHECK_FIELD_OFFSET(ffi_closure, user_data, 4*3);
+
+#define CLOSURE__wrapper(addr) DEREF_U32(addr, 0)
+#define CLOSURE__cif(addr) DEREF_U32(addr, 1)
+#define CLOSURE__fun(addr) DEREF_U32(addr, 2)
+#define CLOSURE__user_data(addr) DEREF_U32(addr, 3)
+
+EM_JS_MACROS(void *, ffi_closure_alloc_js, (size_t size, void **code), {
+  var closure = _malloc(size);
+  var index = getEmptyTableSlot();
+  DEREF_U32(code, 0) = index;
+  CLOSURE__wrapper(closure) = index;
+  return closure;
+})
+
+void * __attribute__ ((visibility ("default")))
+ffi_closure_alloc(size_t size, void **code) {
+  return ffi_closure_alloc_js(size, code);
+}
+
+EM_JS_MACROS(void, ffi_closure_free_js, (void *closure), {
+  var index = CLOSURE__wrapper(closure);
+  freeTableIndexes.push(index);
+  _free(closure);
+})
+
+void __attribute__ ((visibility ("default")))
+ffi_closure_free(void *closure) {
+  return ffi_closure_free_js(closure);
+}
+
+#if !WASM_BIGINT
+
+// When !WASM_BIGINT, we assume there is no JS bigint integration, so JavaScript
+// functions cannot take 64 bit integer arguments.
+//
+// We need to make our own wasm legalizer adaptor that splits 64 bit integer
+// arguments and then calls the JavaScript trampoline, then the JavaScript
+// trampoline reassembles them, calls the closure, then splits the result (if
+// it's a 64 bit integer) and the adaptor puts it back together.
+//
+// This is basically the reverse of the Emscripten function
+// createDyncallWrapper.
+EM_JS(void, createLegalizerWrapper, (int trampoline, int sig), {
+  if(!sig.includes("j")) {
+    return convertJsFunctionToWasm(trampoline, sig);
+  }
+  var sections = [];
+  var prelude = [
+    0x00, 0x61, 0x73, 0x6d, // magic ("\0asm")
+    0x01, 0x00, 0x00, 0x00, // version: 1
+  ];
+  sections.push(prelude);
+  var wrappersig = [
+    // if return type is j, we will put the upper 32 bits into tempRet0.
+    sig[0].replace("j", "i"),
+    // in the rest of the argument list, one 64 bit integer is legalized into
+    // two 32 bit integers.
+    sig.slice(1).replace(/j/g, "ii"),
+  ].join("");
+
+  var typeSectionBody = [
+    0x03, // number of types = 3
+  ];
+  generateFuncType(wrappersig, typeSectionBody); // The signature of the wrapper we are generating
+  generateFuncType(sig, typeSectionBody); // the signature of the function pointer we will call
+  generateFuncType("i", typeSectionBody); // the signature of getTempRet0
+
+  var typeSection = [0x01 /* Type section code */];
+  uleb128Encode(typeSectionBody.length, typeSection); // length of section in bytes
+  typeSection.push.apply(typeSection, typeSectionBody);
+  sections.push(typeSection);
+
+  var importSection = [
+    0x02, // import section code
+    0x0d, // length of section in bytes
+    0x02, // number of imports = 2
+    // Import the getTempRet0 function, which we will call "r"
+    0x01, 0x65, // name "e"
+    0x01, 0x72, // name "r"
+    0x00, // importing a function
+    0x02, // type 2 = () -> i32
+    // Import the wrapped function, which we will call "f"
+    0x01, 0x65, // name "e"
+    0x01, 0x66, // name "f"
+    0x00, // importing a function
+    0x00, // type 0 = wrappersig
+  ];
+  sections.push(importSection);
+
+  var functionSection = [
+    0x03, // function section code
+    0x02, // length of section in bytes
+    0x01, // number of functions = 1
+    0x01, // type 1 = sig
+  ];
+  sections.push(functionSection);
+
+  var exportSection = [
+    0x07, // export section code
+    0x05, // length of section in bytes
+    0x01, // One export
+    0x01, 0x66, // name "f"
+    0x00, // type: function
+    0x02, // function index 2 = the wrapper function
+  ];
+  sections.push(exportSection);
+
+  var convert_code = [];
+  convert_code.push(0x00); // no local variables (except the arguments)
+
+  function localGet(j) {
+    convert_code.push(0x20); // local.get
+    uleb128Encode(j, convert_code);
+  }
+
+  for (var i = 1; i < sig.length; i++) {
+    if (sig[i] == "j") {
+      localGet(i - 1);
+      convert_code.push(
+        0xa7 // i32.wrap_i64
+      );
+      localGet(i - 1);
+      convert_code.push(
+        0x42, 0x20, // i64.const 32
+        0x88,       // i64.shr_u
+        0xa7        // i32.wrap_i64
+      );
+    } else {
+      localGet(i - 1);
+    }
+  }
+  convert_code.push(
+    0x10, 0x01 // call f
+  );
+  if (sig[0] === "j") {
+    // Need to reassemble a 64 bit integer. Lower 32 bits is on stack. Upper 32
+    // bits we get from getTempRet0
+    convert_code.push(
+      0xad,       // i64.extend_i32_unsigned
+      0x10, 0x00, // Call function 0 (r = getTempRet0)
+      // join lower 32 bits and upper 32 bits
+      0xac,       // i64.extend_i32_signed
+      0x42, 0x20, // i64.const 32
+      0x86,       // i64.shl,
+      0x84        // i64.or
+    );
+  }
+  convert_code.push(0x0b); // end
+
+  var codeBody = [0x01]; // one code
+  uleb128Encode(convert_code.length, codeBody);
+  codeBody.push.apply(codeBody, convert_code);
+  var codeSection = [0x0a /* Code section code */];
+  uleb128Encode(codeBody.length, codeSection);
+  codeSection.push.apply(codeSection, codeBody);
+  sections.push(codeSection);
+
+  var bytes = new Uint8Array([].concat.apply([], sections));
+  // We can compile this wasm module synchronously because it is small.
+  var module = new WebAssembly.Module(bytes);
+  var instance = new WebAssembly.Instance(module, {
+    e: {
+      r: getTempRet0,
+      f: trampoline,
+    },
+  });
+  return instance.exports.f;
+});
+#endif
+
+EM_JS_MACROS(
+ffi_status,
+ffi_prep_closure_loc_js,
+(ffi_closure *closure, ffi_cif *cif, void *fun, void *user_data, void *codeloc),
+{
+  var abi = CIF__ABI(cif);
+  var nargs = CIF__NARGS(cif);
+  var nfixedargs = CIF__NFIXEDARGS(cif);
+  var arg_types_ptr = CIF__ARGTYPES(cif);
+  var rtype_unboxed = unbox_small_structs(CIF__RTYPE(cif));
+  var rtype_ptr = rtype_unboxed[0];
+  var rtype_id = rtype_unboxed[1];
+
+  // First construct the signature of the javascript trampoline we are going to create.
+  // Important: this is the signature for calling us, the onward call always has sig viiii.
+  var sig;
+  var ret_by_arg = false;
+  switch (rtype_id) {
+  case FFI_TYPE_VOID:
+    sig = 'v';
+    break;
+  case FFI_TYPE_STRUCT:
+  case FFI_TYPE_LONGDOUBLE:
+    // Return via a first pointer argument.
+    sig = 'vi';
+    ret_by_arg = true;
+    break;
+  case FFI_TYPE_INT:
+  case FFI_TYPE_UINT8:
+  case FFI_TYPE_SINT8:
+  case FFI_TYPE_UINT16:
+  case FFI_TYPE_SINT16:
+  case FFI_TYPE_UINT32:
+  case FFI_TYPE_SINT32:
+  case FFI_TYPE_POINTER:
+    sig = 'i';
+    break;
+  case FFI_TYPE_FLOAT:
+    sig = 'f';
+    break;
+  case FFI_TYPE_DOUBLE:
+    sig = 'd';
+    break;
+  case FFI_TYPE_UINT64:
+  case FFI_TYPE_SINT64:
+    sig = 'j';
+    break;
+  case FFI_TYPE_COMPLEX:
+    throw new Error('complex ret marshalling nyi');
+  default:
+    throw new Error('Unexpected rtype ' + rtype_id);
+  }
+  var unboxed_arg_type_id_list = [];
+  var unboxed_arg_type_info_list = [];
+  for (var i = 0; i < nargs; i++) {
+    var arg_unboxed = unbox_small_structs(DEREF_U32(arg_types_ptr, i));
+    var arg_type_ptr = arg_unboxed[0];
+    var arg_type_id = arg_unboxed[1];
+    unboxed_arg_type_id_list.push(arg_type_id);
+    unboxed_arg_type_info_list.push([FFI_TYPE__SIZE(arg_type_ptr), FFI_TYPE__ALIGN(arg_type_ptr)]);
+  }
+  for (var i = 0; i < nfixedargs; i++) {
+    switch (unboxed_arg_type_id_list[i]) {
+    case FFI_TYPE_INT:
+    case FFI_TYPE_UINT8:
+    case FFI_TYPE_SINT8:
+    case FFI_TYPE_UINT16:
+    case FFI_TYPE_SINT16:
+    case FFI_TYPE_UINT32:
+    case FFI_TYPE_SINT32:
+    case FFI_TYPE_POINTER:
+    case FFI_TYPE_STRUCT:
+      sig += 'i';
+      break;
+    case FFI_TYPE_FLOAT:
+      sig += 'f';
+      break;
+    case FFI_TYPE_DOUBLE:
+      sig += 'd';
+      break;
+    case FFI_TYPE_LONGDOUBLE:
+      sig += 'jj';
+      break;
+    case FFI_TYPE_UINT64:
+    case FFI_TYPE_SINT64:
+      sig += 'j';
+      break;
+    case FFI_TYPE_COMPLEX:
+      throw new Error('complex marshalling nyi');
+    default:
+      throw new Error('Unexpected argtype ' + arg_type_id);
+    }
+  }
+  if (nfixedargs < nargs) {
+    // extra pointer to varargs stack
+    sig += "i";
+  }
+  LOG_DEBUG("CREATE_CLOSURE",  "sig:", sig);
+  function trampoline() {
+    var args = Array.prototype.slice.call(arguments);
+    var size = 0;
+    var orig_stack_ptr = stackSave();
+    var cur_ptr = orig_stack_ptr;
+    var ret_ptr;
+    var jsarg_idx = 0;
+    // Should we return by argument or not? The onwards call returns by argument
+    // no matter what. (Warning: ret_by_arg means the opposite in ffi_call)
+    if (ret_by_arg) {
+      ret_ptr = args[jsarg_idx++];
+    } else {
+      // We might return 4 bytes or 8 bytes, allocate 8 just in case.
+      STACK_ALLOC(cur_ptr, 8, 8);
+      ret_ptr = cur_ptr;
+    }
+    cur_ptr -= 4 * nargs;
+    var args_ptr = cur_ptr;
+    var carg_idx = 0;
+    // Here we either have the actual argument, or a pair of BigInts for long
+    // double, or a pointer to struct. We have to store into args_ptr[i] a
+    // pointer to the ith argument. If the argument is a struct, just store the
+    // pointer. Otherwise allocate stack space and copy the js argument onto the
+    // stack.
+    for (; carg_idx < nfixedargs; carg_idx++) {
+      // jsarg_idx might start out as 0 or 1 depending on ret_by_arg
+      // it advances an extra time for long double
+      var cur_arg = args[jsarg_idx++];
+      var arg_type_info = unboxed_arg_type_info_list[carg_idx];
+      var arg_size = arg_type_info[0];
+      var arg_align = arg_type_info[1];
+      var arg_type_id = unboxed_arg_type_id_list[carg_idx];
+      switch (arg_type_id) {
+      case FFI_TYPE_UINT8:
+      case FFI_TYPE_SINT8:
+        // Bad things happen if we don't align to 4 here
+        STACK_ALLOC(cur_ptr, 1, 4);
+        DEREF_U32(args_ptr, carg_idx) = cur_ptr;
+        DEREF_U8(cur_ptr, 0) = cur_arg;
+        break;
+      case FFI_TYPE_UINT16:
+      case FFI_TYPE_SINT16:
+        // Bad things happen if we don't align to 4 here
+        STACK_ALLOC(cur_ptr, 2, 4);
+        DEREF_U32(args_ptr, carg_idx) = cur_ptr;
+        DEREF_U16(cur_ptr, 0) = cur_arg;
+        break;
+      case FFI_TYPE_INT:
+      case FFI_TYPE_UINT32:
+      case FFI_TYPE_SINT32:
+      case FFI_TYPE_POINTER:
+        STACK_ALLOC(cur_ptr, 4, 4);
+        DEREF_U32(args_ptr, carg_idx) = cur_ptr;
+        DEREF_U32(cur_ptr, 0) = cur_arg;
+        break;
+      case FFI_TYPE_STRUCT:
+        // cur_arg is already a pointer to struct
+        // copy it onto stack to pass by value
+        STACK_ALLOC(cur_ptr, arg_size, arg_align);
+        HEAP8.subarray(cur_ptr, cur_ptr + arg_size).set(HEAP8.subarray(cur_arg, cur_arg + arg_size));
+        DEREF_U32(args_ptr, carg_idx) = cur_ptr;
+        break;
+      case FFI_TYPE_FLOAT:
+        STACK_ALLOC(cur_ptr, 4, 4);
+        DEREF_U32(args_ptr, carg_idx) = cur_ptr;
+        DEREF_F32(cur_ptr, 0) = cur_arg;
+        break;
+      case FFI_TYPE_DOUBLE:
+        STACK_ALLOC(cur_ptr, 8, 8);
+        DEREF_U32(args_ptr, carg_idx) = cur_ptr;
+        DEREF_F64(cur_ptr, 0) = cur_arg;
+        break;
+      case FFI_TYPE_UINT64:
+      case FFI_TYPE_SINT64:
+        STACK_ALLOC(cur_ptr, 8, 8);
+        DEREF_U32(args_ptr, carg_idx) = cur_ptr;
+        #if WASM_BIGINT
+        DEREF_U64(cur_ptr, 0) = cur_arg;
+        #else
+        // Bigint arg was split by legalizer adaptor
+        DEREF_U32(cur_ptr, 0) = cur_arg;
+        cur_arg = args[jsarg_idx++];
+        DEREF_U32(cur_ptr, 1) = cur_arg;
+        #endif
+        break;
+      case FFI_TYPE_LONGDOUBLE:
+        STACK_ALLOC(cur_ptr, 16, 8);
+        DEREF_U32(args_ptr, carg_idx) = cur_ptr;
+        #if WASM_BIGINT
+        DEREF_U64(cur_ptr, 0) = cur_arg;
+        cur_arg = args[jsarg_idx++];
+        DEREF_U64(cur_ptr, 1) = cur_arg;
+        #else
+        // Was split by legalizer adaptor
+        DEREF_U32(cur_ptr, 0) = cur_arg;
+        cur_arg = args[jsarg_idx++];
+        DEREF_U32(cur_ptr, 1) = cur_arg;
+        cur_arg = args[jsarg_idx++];
+        DEREF_U32(cur_ptr, 2) = cur_arg;
+        cur_arg = args[jsarg_idx++];
+        DEREF_U32(cur_ptr, 3) = cur_arg;
+        #endif
+        break;
+      }
+    }
+    // If its a varargs call, last js argument is a pointer to the varargs.
+    var varargs = args[args.length - 1];
+    // We have no way of knowing how many varargs were actually provided, this
+    // fills the rest of the stack space allocated with nonsense. The onward
+    // call will know to ignore the nonsense.
+
+    // We either have a pointer to the argument if the argument is not a struct
+    // or a pointer to pointer to struct. We need to store a pointer to the
+    // argument into args_ptr[i]
+    for (; carg_idx < nargs; carg_idx++) {
+      var arg_type_id = unboxed_arg_type_id_list[carg_idx];
+      var arg_type_info = unboxed_arg_type_info_list[carg_idx];
+      var arg_size = arg_type_info[0];
+      var arg_align = arg_type_info[1];
+      if (arg_type_id === FFI_TYPE_STRUCT) {
+        // In this case varargs is a pointer to pointer to struct so we need to
+        // deref once
+        var struct_ptr = DEREF_U32(varargs, 0);
+        STACK_ALLOC(cur_ptr, arg_size, arg_align);
+        HEAP8.subarray(cur_ptr, cur_ptr + arg_size).set(HEAP8.subarray(struct_ptr, struct_ptr + arg_size));
+        DEREF_U32(args_ptr, carg_idx) = cur_ptr;
+      } else {
+        DEREF_U32(args_ptr, carg_idx) = varargs;
+      }
+      varargs += 4;
+    }
+    stackRestore(cur_ptr);
+    stackAlloc(0); // stackAlloc enforces alignment invariants on the stack pointer
+    LOG_DEBUG("CALL_CLOSURE",  "closure:", closure, "fptr", CLOSURE__fun(closure), "cif",  CLOSURE__cif(closure));
+    getWasmTableEntry(CLOSURE__fun(closure))(
+        CLOSURE__cif(closure), ret_ptr, args_ptr,
+        CLOSURE__user_data(closure)
+    );
+    stackRestore(orig_stack_ptr);
+
+    // If we aren't supposed to return by argument, figure out what to return.
+    if (!ret_by_arg) {
+      switch (sig[0]) {
+      case "i":
+        return DEREF_U32(ret_ptr, 0);
+      case "j":
+        #if WASM_BIGINT
+        return DEREF_U64(ret_ptr, 0);
+        #else
+        // Split the return i64, set the upper 32 bits into tempRet0 and return
+        // the lower 32 bits.
+        setTempRet0(DEREF_U32(ret_ptr, 1));
+        return DEREF_U32(ret_ptr, 0);
+        #endif
+      case "d":
+        return DEREF_F64(ret_ptr, 0);
+      case "f":
+        return DEREF_F32(ret_ptr, 0);
+      }
+    }
+  }
+  try {
+    var wasm_trampoline = JS_FUNCTION_TO_WASM(trampoline, sig);
+  } catch(e) {
+    return FFI_BAD_TYPEDEF_MACRO;
+  }
+  setWasmTableEntry(codeloc, wasm_trampoline);
+  CLOSURE__cif(closure) = cif;
+  CLOSURE__fun(closure) = fun;
+  CLOSURE__user_data(closure) = user_data;
+  return FFI_OK_MACRO;
+})
+
+// EM_JS does not correctly handle function pointer arguments, so we need a
+// helper
+ffi_status ffi_prep_closure_loc(ffi_closure *closure, ffi_cif *cif,
+                                void (*fun)(ffi_cif *, void *, void **, void *),
+                                void *user_data, void *codeloc) {
+  if (cif->abi != FFI_WASM32_EMSCRIPTEN)
+    return FFI_BAD_ABI;
+  return ffi_prep_closure_loc_js(closure, cif, (void *)fun, user_data,
+                                     codeloc);
+}
diff --git a/src/wasm32/ffitarget.h b/src/wasm32/ffitarget.h
new file mode 100644
index 0000000..ac78b74
--- /dev/null
+++ b/src/wasm32/ffitarget.h
@@ -0,0 +1,62 @@
+/* -----------------------------------------------------------------*-C-*-
+   ffitarget.h - Copyright (c) 2018-2023  Hood Chatham, Brion Vibber, Kleis Auke Wolthuizen, and others.
+
+   Target configuration macros for wasm32.
+
+   Permission is hereby granted, free of charge, to any person obtaining
+   a copy of this software and associated documentation files (the
+   ``Software''), to deal in the Software without restriction, including
+   without limitation the rights to use, copy, modify, merge, publish,
+   distribute, sublicense, and/or sell copies of the Software, and to
+   permit persons to whom the Software is furnished to do so, subject to
+   the following conditions:
+
+   The above copyright notice and this permission notice shall be included
+   in all copies or substantial portions of the Software.
+
+   THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
+   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+   NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+   DEALINGS IN THE SOFTWARE.
+
+   ----------------------------------------------------------------------- */
+
+#ifndef LIBFFI_TARGET_H
+#define LIBFFI_TARGET_H
+
+#ifndef LIBFFI_H
+#error "Please do not include ffitarget.h directly into your source.  Use ffi.h instead."
+#endif
+
+/* ---- Generic type definitions ----------------------------------------- */
+
+typedef unsigned long ffi_arg;
+typedef signed long ffi_sarg;
+
+// TODO: https://github.com/emscripten-core/emscripten/issues/9868
+typedef void (*ffi_fp)(void);
+
+typedef enum ffi_abi {
+  FFI_FIRST_ABI = 0,
+  FFI_WASM32, // "raw", no structures, varargs, or closures (not implemented!)
+  FFI_WASM32_EMSCRIPTEN, // structures, varargs, and split 64-bit params
+  FFI_LAST_ABI,
+#ifdef __EMSCRIPTEN__
+  FFI_DEFAULT_ABI = FFI_WASM32_EMSCRIPTEN
+#else
+  FFI_DEFAULT_ABI = FFI_WASM32
+#endif
+} ffi_abi;
+
+#define FFI_CLOSURES 1
+// #define FFI_GO_CLOSURES 0
+#define FFI_TRAMPOLINE_SIZE 4
+// #define FFI_NATIVE_RAW_API 0
+#define FFI_TARGET_SPECIFIC_VARIADIC 1
+#define FFI_EXTRA_CIF_FIELDS  unsigned int nfixedargs
+
+#endif
diff --git a/testsuite/emscripten/build-tests.sh b/testsuite/emscripten/build-tests.sh
new file mode 100755
index 0000000..6b9d5ba
--- /dev/null
+++ b/testsuite/emscripten/build-tests.sh
@@ -0,0 +1,40 @@
+#!/usr/bin/env bash
+emcc_exists="$(command -v emcc)"
+if [ ! "${emcc_exists}" ]; then
+  echo "Emscripten not on path"
+  exit 1
+fi
+
+set -e
+
+cd "$1"
+export CFLAGS="-fPIC -O2 -I../../target/include $EXTRA_CFLAGS"
+export CXXFLAGS="$CFLAGS -sNO_DISABLE_EXCEPTION_CATCHING $EXTRA_CXXFLAGS"
+export LDFLAGS=" \
+    -L../../target/lib/ -lffi \
+    -sEXPORT_ALL \
+    -sMODULARIZE \
+    -sMAIN_MODULE \
+    -sSTRICT_JS \
+    -sNO_DISABLE_EXCEPTION_CATCHING \
+    $EXTRA_LD_FLAGS \
+"
+
+# This needs to test false if there exists an environment variable called
+# WASM_BIGINT whose contents are empty. Don't use +x.
+if [ -n "${WASM_BIGINT}" ] ; then
+  export LDFLAGS+=" -sWASM_BIGINT"
+else
+  export LDFLAGS+=" -sEXPORTED_RUNTIME_METHODS='getTempRet0,setTempRet0'"
+fi
+
+# Rename main functions to test__filename so we can link them together
+ls *c | sed 's!\(.*\)\.c!sed -i "s/main/test__\1/g" \0!g' | bash
+
+# Compile
+ls *.c | sed 's/\(.*\)\.c/emcc $CFLAGS -c \1.c -o \1.o /g' | bash
+ls *.cc | sed 's/\(.*\)\.cc/em++ $CXXFLAGS -c \1.cc -o \1.o /g' | bash
+
+# Link
+em++ $LDFLAGS *.o -o test.js
+cp ../emscripten/test.html .
diff --git a/testsuite/emscripten/build.sh b/testsuite/emscripten/build.sh
new file mode 100755
index 0000000..32596c3
--- /dev/null
+++ b/testsuite/emscripten/build.sh
@@ -0,0 +1,63 @@
+#!/usr/bin/env bash
+command -v emcc >/dev/null 2>&1 || {
+  echo >&2 "emsdk could not be found.  Aborting."
+  exit 1
+}
+
+set -e
+
+SOURCE_DIR=$PWD
+
+# Working directories
+TARGET=$SOURCE_DIR/target
+mkdir -p "$TARGET"
+
+# Define default arguments
+
+# JS BigInt to Wasm i64 integration, disabled by default
+# This needs to test false if there exists an environment variable called
+# WASM_BIGINT whose contents are empty. Don't use +x.
+if [ -n "${WASM_BIGINT}" ]; then
+  WASM_BIGINT=true
+else
+  WASM_BIGINT=false
+fi
+
+# Parse arguments
+while [ $# -gt 0 ]; do
+  case $1 in
+  --enable-wasm-bigint) WASM_BIGINT=true ;;
+  --debug) DEBUG=true ;;
+  *)
+    echo "ERROR: Unknown parameter: $1" >&2
+    exit 1
+    ;;
+  esac
+  shift
+done
+
+# Common compiler flags
+export CFLAGS="-O3 -fPIC"
+if [ "$WASM_BIGINT" = "true" ]; then
+  # We need to detect WASM_BIGINT support at compile time
+  export CFLAGS+=" -DWASM_BIGINT"
+fi
+if [ "$DEBUG" = "true" ]; then
+  export CFLAGS+=" -DDEBUG_F"
+fi
+export CXXFLAGS="$CFLAGS"
+
+# Build paths
+export CPATH="$TARGET/include"
+export PKG_CONFIG_PATH="$TARGET/lib/pkgconfig"
+export EM_PKG_CONFIG_PATH="$PKG_CONFIG_PATH"
+
+# Specific variables for cross-compilation
+export CHOST="wasm32-unknown-linux" # wasm32-unknown-emscripten
+
+autoreconf -fiv
+emconfigure ./configure --host=$CHOST --prefix="$TARGET" --enable-static --disable-shared --disable-dependency-tracking \
+  --disable-builddir --disable-multi-os-directory --disable-raw-api --disable-docs
+make install
+cp fficonfig.h target/include/
+cp include/ffi_common.h target/include/
diff --git a/testsuite/emscripten/conftest.py b/testsuite/emscripten/conftest.py
new file mode 100644
index 0000000..57fac80
--- /dev/null
+++ b/testsuite/emscripten/conftest.py
@@ -0,0 +1,80 @@
+from pathlib import Path
+from pytest import fixture
+from pytest_pyodide.server import spawn_web_server
+from pytest_pyodide import runner
+
+TEST_PATH = Path(__file__).parents[1].resolve()
+
+
+class BaseRunner(runner._BrowserBaseRunner):
+    def __init__(
+        self,
+        *args,
+        test_dir,
+        **kwargs,
+    ):
+        self.test_dir = test_dir
+        super().__init__(
+            *args,
+            **kwargs,
+            load_pyodide=False,
+        )
+
+    def prepare_driver(self):
+        self.base_url = (
+            f"http://{self.server_hostname}:{self.server_port}/{self.test_dir}/"
+        )
+        self.goto(f"{self.base_url}/test.html")
+
+    def javascript_setup(self):
+        self.run_js("globalThis.TestModule = await globalThis.Module();")
+
+
+class FirefoxRunner(BaseRunner, runner.SeleniumFirefoxRunner):
+    pass
+
+
+class ChromeRunner(BaseRunner, runner.SeleniumChromeRunner):
+    pass
+
+
+# TODO: Figure out how to get NodeRunner to work.
+
+RUNNER_DICT = {x.browser: x for x in [FirefoxRunner, ChromeRunner]}
+
+
+@fixture(params=list(RUNNER_DICT), scope="class")
+def selenium_class_scope(request, web_server_main):
+    server_hostname, server_port, server_log = web_server_main
+    assert request.param in RUNNER_DICT
+    cls = RUNNER_DICT[request.param]
+    selenium = cls(
+        test_dir=request.cls.TEST_BUILD_DIR,
+        server_port=server_port,
+        server_hostname=server_hostname,
+        server_log=server_log,
+    )
+    request.cls.call_number = 0
+    try:
+        yield selenium
+    finally:
+        print(selenium.logs)
+        selenium.driver.quit()
+
+
+@fixture(scope="function")
+def selenium(selenium_class_scope, request):
+    selenium = selenium_class_scope
+    request.cls.call_number += 1
+    # Refresh page every 50 calls to prevent firefox out of memory errors
+    if request.cls.call_number % 50 == 0:
+        selenium.driver.refresh()
+        selenium.javascript_setup()
+    selenium.clean_logs()
+    yield selenium
+
+
+@fixture(scope="session")
+def web_server_main(request):
+    with spawn_web_server(TEST_PATH) as output:
+        yield output
diff --git a/testsuite/emscripten/node-tests.sh b/testsuite/emscripten/node-tests.sh
new file mode 100755
index 0000000..2ab79e8
--- /dev/null
+++ b/testsuite/emscripten/node-tests.sh
@@ -0,0 +1,48 @@
+#!/bin/bash
+
+# JS BigInt to Wasm i64 integration, disabled by default
+WASM_BIGINT=false
+
+emcc_exists="$(command -v emcc)"
+if [ ! "${emcc_exists}" ]; then
+  echo "Emscripten not on path"
+  exit 1
+fi
+
+# Parse arguments
+while [ $# -gt 0 ]; do
+  case $1 in
+  --enable-wasm-bigint) WASM_BIGINT=true ;;
+  *)
+    echo "ERROR: Unknown parameter: $1" >&2
+    exit 1
+    ;;
+  esac
+  shift
+done
+
+# Common compiler flags
+export CFLAGS="-fPIC $EXTRA_CFLAGS"
+if [ "$WASM_BIGINT" = "true" ]; then
+  # We need to detect WASM_BIGINT support at compile time
+  export CFLAGS+=" -DWASM_BIGINT"
+fi
+export CXXFLAGS="$CFLAGS -sNO_DISABLE_EXCEPTION_CATCHING $EXTRA_CXXFLAGS"
+export LDFLAGS="-sEXPORTED_FUNCTIONS=_main,_malloc,_free -sALLOW_TABLE_GROWTH -sASSERTIONS -sNO_DISABLE_EXCEPTION_CATCHING"
+if [ "$WASM_BIGINT" = "true" ]; then
+  export LDFLAGS+=" -sWASM_BIGINT"
+else
+  export LDFLAGS+=" -sEXPORTED_RUNTIME_METHODS='getTempRet0,setTempRet0'"
+fi
+
+# Specific variables for cross-compilation
+export CHOST="wasm32-unknown-linux" # wasm32-unknown-emscripten
+
+autoreconf -fiv
+emconfigure ./configure --prefix="$(pwd)/target" --host=$CHOST --enable-static --disable-shared \
+  --disable-builddir --disable-multi-os-directory --disable-raw-api --disable-docs ||
+  (cat config.log && exit 1)
+make
+
+EMMAKEN_JUST_CONFIGURE=1 emmake make check \
+  RUNTESTFLAGS="LDFLAGS_FOR_TARGET='$LDFLAGS'" || (cat testsuite/libffi.log && exit 1)
diff --git a/testsuite/emscripten/quiet_emcc_info.py b/testsuite/emscripten/quiet_emcc_info.py
new file mode 100644
index 0000000..b2b3f06
--- /dev/null
+++ b/testsuite/emscripten/quiet_emcc_info.py
@@ -0,0 +1,36 @@
+"""
+Prevent emcc from printing info level logging
+
+dejagnu will fail tests because of these log statements and the messages depend
+on emscripten cache state so xfailing the right tests is very hard.
+
+See emscripten issue:
+https://github.com/emscripten-core/emscripten/issues/18607
+"""
+
+from pathlib import Path
+from shutil import which
+from sys import exit
+from textwrap import dedent
+
+EMCC_PATH = Path(which("emcc") + ".py")
+
+emcc_text = EMCC_PATH.read_text()
+if "# quiet_emcc_info patch" in emcc_text:
+    exit(0)
+
+emcc_lines = emcc_text.splitlines()
+emcc_lines.insert(
+    1,
+    dedent(
+        """
+        # quiet_emcc_info patch
+        import logging
+        for name in ["cache", "system_libs", "shared"]:
+            logger = logging.getLogger(name)
+            logger.setLevel(logging.WARN)
+        """
+    ),
+)
+
+EMCC_PATH.write_text("\n".join(emcc_lines))
diff --git a/testsuite/emscripten/test.html b/testsuite/emscripten/test.html
new file mode 100644
index 0000000..7701503
--- /dev/null
+++ b/testsuite/emscripten/test.html
@@ -0,0 +1,7 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <script src="test.js"></script>
+  </head>
+  <body></body>
+</html>
diff --git a/testsuite/emscripten/test_libffi.py b/testsuite/emscripten/test_libffi.py
new file mode 100644
index 0000000..059d535
--- /dev/null
+++ b/testsuite/emscripten/test_libffi.py
@@ -0,0 +1,51 @@
+import subprocess
+import pathlib
+import pytest
+
+TEST_PATH = pathlib.Path(__file__).parents[1].resolve()
+
+xfails = {}
+
+
+def libffi_tests(self, selenium, libffi_test):
+    if libffi_test in xfails:
+        pytest.xfail(f'known failure with code "{xfails[libffi_test]}"')
+    res = selenium.run_js(
+        """
+        window.TestModule = await Module();
+        """
+    )
+    selenium.run_js(
+        f"""
+        try {{
+            TestModule._test__{libffi_test}();
+        }} catch(e){{
+            if(e.name !== "ExitStatus"){{
+                throw e;
+            }}
+            if(e.status !== 0){{
+                throw new Error(`Terminated with nonzero status code ${{e.status}}: ` + e.message);
+            }}
+        }}
+        """
+    )
+
+
+class TestCall:
+    TEST_BUILD_DIR = "libffi.call.test"
+    test_call = libffi_tests
+
+
+class TestClosures:
+    TEST_BUILD_DIR = "libffi.closures.test"
+    test_closures = libffi_tests
+
+
+def pytest_generate_tests(metafunc):
+    test_build_dir = metafunc.cls.TEST_BUILD_DIR
+    test_names = [x.stem for x in (TEST_PATH / test_build_dir).glob("*.o")]
+    metafunc.parametrize("libffi_test", test_names)
+
+
+if __name__ == "__main__":
+    subprocess.call(["build-tests.sh", "libffi.call"])
diff --git a/testsuite/lib/libffi.exp b/testsuite/lib/libffi.exp
index 17d1ed5..a84e533 100644
--- a/testsuite/lib/libffi.exp
+++ b/testsuite/lib/libffi.exp
@@ -221,6 +221,13 @@ proc libffi-dg-test-1 { target_compile prog do_what extra_tool_flags } {
 	set output_match [lreplace $output_match 1 1 $x]
     }
 
+    if { [ istarget "wasm32-*-*" ] } {
+        # emscripten will get confused if told to build as .exe
+        set exec_suffix ""
+    } else {
+        set exec_suffix ".exe"
+    }
+
     # Set up the compiler flags, based on what we're going to do.
 
     set options [list]
@@ -231,7 +238,7 @@ proc libffi-dg-test-1 { target_compile prog do_what extra_tool_flags } {
 	}
 	"link" {
 	    set compile_type "executable"
-	    set output_file "[file rootname [file tail $prog]].exe"
+	    set output_file "[file rootname [file tail $prog]]$exec_suffix"
 	    # The following line is needed for targets like the i960 where
 	    # the default output file is b.out.  Sigh.
 	}
@@ -240,7 +247,7 @@ proc libffi-dg-test-1 { target_compile prog do_what extra_tool_flags } {
 	    # FIXME: "./" is to cope with "." not being in $PATH.
 	    # Should this be handled elsewhere?
 	    # YES.
-	    set output_file "./[file rootname [file tail $prog]].exe"
+	    set output_file "./[file rootname [file tail $prog]]$exec_suffix"
 	    # This is the only place where we care if an executable was
 	    # created or not.  If it was, dg.exp will try to run it.
 	    remote_file build delete $output_file;
@@ -417,6 +424,12 @@ proc libffi_target_compile { source dest type options } {
         }
     }
 
+    # emscripten emits this warning while building the feature test
+    # which causes it to be seen as unsupported.
+    if { [string match "wasm32-*" $target_triplet] } {
+        lappend options "additional_flags=-Wno-unused-command-line-argument"
+    }
+
     verbose "options: $options"
     return [target_compile $source $dest $type $options]
 }
diff --git a/testsuite/libffi.call/bpo-38748.c b/testsuite/libffi.call/bpo-38748.c
deleted file mode 100644
index 294bda0..0000000
--- a/testsuite/libffi.call/bpo-38748.c
+++ /dev/null
@@ -1,41 +0,0 @@
-/* Area:	bpo-38748
-   Purpose:	test for stdcall alignment problem
-   Source:      github.com/python/cpython/pull/26204 */
-
-/* { dg-do run } */
-
-#include "ffitest.h"
-#include "ffi_common.h"
-
-static UINT32 ABI_ATTR align_arguments(UINT32 l1,
-				       UINT64 l2)
-{
-  return l1 + (UINT32) l2;
-}
-
-int main(void)
-{
-  ffi_cif cif;
-  ffi_type *args[4] = {
-    &ffi_type_uint32,
-    &ffi_type_uint64
-  };
-  ffi_arg lr1, lr2;
-  UINT32 l1 = 1;
-  UINT64 l2 = 2;
-  void *values[2] = {&l1, &l2};
-
-  /* Initialize the cif */
-  CHECK(ffi_prep_cif(&cif, ABI_NUM, 2,
-		     &ffi_type_uint32, args) == FFI_OK);
-
-  lr1 = align_arguments(l1, l2);
-
-  ffi_call(&cif, FFI_FN(align_arguments), &lr2, values);
-
-  if (lr1 == lr2)
-    printf("bpo-38748 arguments tests ok!\n");
-  else
-    CHECK(0);
-  exit(0);
-}
diff --git a/testsuite/libffi.call/bpo_38748.c b/testsuite/libffi.call/bpo_38748.c
new file mode 100644
index 0000000..294bda0
--- /dev/null
+++ b/testsuite/libffi.call/bpo_38748.c
@@ -0,0 +1,41 @@
+/* Area:	bpo-38748
+   Purpose:	test for stdcall alignment problem
+   Source:      github.com/python/cpython/pull/26204 */
+
+/* { dg-do run } */
+
+#include "ffitest.h"
+#include "ffi_common.h"
+
+static UINT32 ABI_ATTR align_arguments(UINT32 l1,
+				       UINT64 l2)
+{
+  return l1 + (UINT32) l2;
+}
+
+int main(void)
+{
+  ffi_cif cif;
+  ffi_type *args[4] = {
+    &ffi_type_uint32,
+    &ffi_type_uint64
+  };
+  ffi_arg lr1, lr2;
+  UINT32 l1 = 1;
+  UINT64 l2 = 2;
+  void *values[2] = {&l1, &l2};
+
+  /* Initialize the cif */
+  CHECK(ffi_prep_cif(&cif, ABI_NUM, 2,
+		     &ffi_type_uint32, args) == FFI_OK);
+
+  lr1 = align_arguments(l1, l2);
+
+  ffi_call(&cif, FFI_FN(align_arguments), &lr2, values);
+
+  if (lr1 == lr2)
+    printf("bpo-38748 arguments tests ok!\n");
+  else
+    CHECK(0);
+  exit(0);
+}
diff --git a/testsuite/libffi.closures/closure_loc_fn0.c b/testsuite/libffi.closures/closure_loc_fn0.c
index 6f2e3d5..f344a60 100644
--- a/testsuite/libffi.closures/closure_loc_fn0.c
+++ b/testsuite/libffi.closures/closure_loc_fn0.c
@@ -7,9 +7,6 @@
    Originator:	<andreast@gcc.gnu.org> 20030828	 */
 
 
-
-
-/* { dg-do run { xfail wasm32*-*-* } } */
 #include "ffitest.h"
 
 static void
@@ -83,7 +80,7 @@ int main (void)
   CHECK(ffi_prep_closure_loc(pcl, &cif, closure_loc_test_fn0,
 			 (void *) 3 /* userdata */, codeloc) == FFI_OK);
 
-#ifndef FFI_EXEC_STATIC_TRAMP
+#if !defined(FFI_EXEC_STATIC_TRAMP) && !defined(__EMSCRIPTEN__)
   /* With static trampolines, the codeloc does not point to closure */
   CHECK(memcmp(pcl, FFI_CL(codeloc), sizeof(*pcl)) == 0);
 #endif
diff --git a/testsuite/libffi.closures/cls_longdouble_va.c b/testsuite/libffi.closures/cls_longdouble_va.c
index 493f0f6..ba32f5c 100644
--- a/testsuite/libffi.closures/cls_longdouble_va.c
+++ b/testsuite/libffi.closures/cls_longdouble_va.c
@@ -9,10 +9,21 @@
 /* { dg-output "" { xfail mips-sgi-irix6* } } PR libffi/46660 */
 
 #include "ffitest.h"
+#include <stdarg.h>
 
 #define BUF_SIZE 50
 static char buffer[BUF_SIZE];
 
+static int
+wrap_printf(char* fmt, ...) {
+	va_list ap;
+	va_start(ap, fmt);
+	long double ldArg = va_arg(ap, long double);
+	va_end(ap);
+	CHECK((int)ldArg == 7);
+	return printf(fmt, ldArg);	
+}
+
 static void
 cls_longdouble_va_fn(ffi_cif* cif __UNUSED__, void* resp,
 		     void** args, void* userdata __UNUSED__)
@@ -50,7 +61,7 @@ int main (void)
 	args[1] = &ldArg;
 	args[2] = NULL;
 
-	ffi_call(&cif, FFI_FN(printf), &res, args);
+	ffi_call(&cif, FFI_FN(wrap_printf), &res, args);
 	/* { dg-output "7.0" } */
 	printf("res: %d\n", (int) res);
 	/* { dg-output "\nres: 4" } */
diff --git a/testsuite/libffi.closures/cls_multi_schar.c b/testsuite/libffi.closures/cls_multi_schar.c
index 921777a..9eb02f9 100644
--- a/testsuite/libffi.closures/cls_multi_schar.c
+++ b/testsuite/libffi.closures/cls_multi_schar.c
@@ -64,7 +64,7 @@ int main (void)
   /* { dg-output "2 125: 127" } */
   printf("res: %d\n", (signed char)res_call);
   /* { dg-output "\nres: 127" } */
-  CHECK(res_call == 127);
+  CHECK((signed char)res_call == 127);
 
   CHECK(ffi_prep_closure_loc(pcl, &cif, test_func_gn, NULL, code)  == FFI_OK);
 
diff --git a/testsuite/libffi.closures/cls_multi_sshort.c b/testsuite/libffi.closures/cls_multi_sshort.c
index d78c62d..9d4db5b 100644
--- a/testsuite/libffi.closures/cls_multi_sshort.c
+++ b/testsuite/libffi.closures/cls_multi_sshort.c
@@ -65,7 +65,7 @@ int main (void)
   /* { dg-output "2 32765: 32767" } */
   printf("res: %d\n", (unsigned short)res_call);
   /* { dg-output "\nres: 32767" } */
-  CHECK(res_call == 32767);
+  CHECK((unsigned short)res_call == 32767);
 
   CHECK(ffi_prep_closure_loc(pcl, &cif, test_func_gn, NULL, code)  == FFI_OK);
 
diff --git a/testsuite/libffi.closures/huge_struct.c b/testsuite/libffi.closures/huge_struct.c
index 71cae26..572a0c8 100644
--- a/testsuite/libffi.closures/huge_struct.c
+++ b/testsuite/libffi.closures/huge_struct.c
@@ -5,7 +5,7 @@
 	Originator:		Blake Chaffin	6/18/2007
 */
 
-/* { dg-do run { xfail strongarm*-*-* xscale*-*-* wasm32*-*-* } } */
+/* { dg-do run { xfail strongarm*-*-* xscale*-*-* } } */
 /* { dg-options -mlong-double-128 { target powerpc64*-*-linux-gnu* } } */
 /* { dg-options -Wformat=0 { target moxie*-*-elf or1k-*-* } } */
 
diff --git a/testsuite/libffi.closures/unwindtest.cc b/testsuite/libffi.closures/unwindtest.cc
index 6c97c61..b643c48 100644
--- a/testsuite/libffi.closures/unwindtest.cc
+++ b/testsuite/libffi.closures/unwindtest.cc
@@ -48,6 +48,7 @@ typedef int (*closure_test_type1)(float, float, float, float, signed short,
 				  float, float, int, double, int, int, float,
 				  int, int, int, int);
 
+extern "C"
 int main (void)
 {
   ffi_cif cif;
diff --git a/testsuite/libffi.closures/unwindtest_ffi_call.cc b/testsuite/libffi.closures/unwindtest_ffi_call.cc
index 153d240..6feaa57 100644
--- a/testsuite/libffi.closures/unwindtest_ffi_call.cc
+++ b/testsuite/libffi.closures/unwindtest_ffi_call.cc
@@ -14,6 +14,7 @@ static int checking(int a __UNUSED__, short b __UNUSED__,
   throw 9;
 }
 
+extern "C"
 int main (void)
 {
   ffi_cif cif;