run tuner only once during CI
diff --git a/.travis.yml b/.travis.yml
index 26b0460..b3b79c0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -143,13 +143,13 @@ matrix:
- env: SANITIZER=1 BUILDOPTIONS='--with-cc=clang-7 --cflags=-DMP_32BIT --with-travis-valgrind'
# Test "autotuning", the automatic evaluation and setting of the Toom-Cook cut-offs.
- - env: SANITIZER=1 BUILDOPTIONS='--with-cc=gcc-5 --cflags=-DMP_8BIT --with-travis-valgrind --make-option=tune'
- - env: SANITIZER=1 BUILDOPTIONS='--with-cc=gcc-5 --cflags=-DMP_16BIT --with-travis-valgrind --make-option=tune'
- - env: SANITIZER=1 BUILDOPTIONS='--with-cc=gcc-5 --cflags=-DMP_32BIT --with-travis-valgrind --make-option=tune'
- - env: SANITIZER=1 BUILDOPTIONS='--with-cc=gcc-5 --with-travis-valgrind --make-option=tune'
- - env: SANITIZER=1 BUILDOPTIONS='--with-cc=clang-7 --cflags=-DMP_8BIT --with-travis-valgrind --make-option=tune'
- - env: SANITIZER=1 BUILDOPTIONS='--with-cc=clang-7 --cflags=-DMP_16BIT --with-travis-valgrind --make-option=tune'
- - env: SANITIZER=1 BUILDOPTIONS='--with-cc=clang-7 --cflags=-DMP_32BIT --with-travis-valgrind --make-option=tune'
+ #- env: SANITIZER=1 BUILDOPTIONS='--with-cc=gcc-5 --cflags=-DMP_8BIT --with-travis-valgrind --make-option=tune'
+ #- env: SANITIZER=1 BUILDOPTIONS='--with-cc=gcc-5 --cflags=-DMP_16BIT --with-travis-valgrind --make-option=tune'
+ #- env: SANITIZER=1 BUILDOPTIONS='--with-cc=gcc-5 --cflags=-DMP_32BIT --with-travis-valgrind --make-option=tune'
+ #- env: SANITIZER=1 BUILDOPTIONS='--with-cc=gcc-5 --with-travis-valgrind --make-option=tune'
+ #- env: SANITIZER=1 BUILDOPTIONS='--with-cc=clang-7 --cflags=-DMP_8BIT --with-travis-valgrind --make-option=tune'
+ #- env: SANITIZER=1 BUILDOPTIONS='--with-cc=clang-7 --cflags=-DMP_16BIT --with-travis-valgrind --make-option=tune'
+ #- env: SANITIZER=1 BUILDOPTIONS='--with-cc=clang-7 --cflags=-DMP_32BIT --with-travis-valgrind --make-option=tune'
- env: SANITIZER=1 BUILDOPTIONS='--with-cc=clang-7 --with-travis-valgrind --make-option=tune'
# GCC for the x86-64 architecture testing against a different Bigint-implementation