kc3-lang/gnulib

2016-06-24T13:35:12

intprops: port better to GCC 7 GCC 7 __builtin_add_overflow supports a new usage form, where the last argument is a null pointer, and which merely returns 1 if an overflow would occur. This is a constant expression if all arguments are constants, and should generate faster code when code needs to be generated. * lib/intprops.h (_GL_HAS_BUILTIN_OVERFLOW_WITH_NULL): New macro. (_GL_ADD_OVERFLOW, _GL_SUBTRACT_OVERFLOW, _GL_MULTIPLY_OVERFLOW): Use builtin operations if available. (INT_NEGATE_OVERFLOW): Prefer INT_SUBTRACT_OVERFLOW if builtin operations are available, as it's almost surely faster.