https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77769
Bug ID: 77769 Summary: function generated for OpenMP region uses wrong instruction set Product: gcc Version: 6.2.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: other Assignee: unassigned at gcc dot gnu.org Reporter: yzhang1985 at gmail dot com Target Milestone: --- Created attachment 39707 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=39707&action=edit compilation will fail with "target specific option mismatch" Greetings, I'm trying write AVX2 SIMD intrinsics code that will be dynamically dispatched at runtime through a function pointer. The code has to work for vanilla x86_64 processors, so I can't use -mavx2. Instead, I use #pragma GCC target("avx2") to target AVX2 for selected functions. The bug is that whenever I call AVX or AVX2 intrinsics inside an OpenMP region, I get the error, "target specific option mismatch" If I move the intrinsics code to another function, it can compile, but if I mark that function with __attribute__((always_inline)), the compilation fails with the same error. So, my conclusion is that the OpenMP code generator is still targeting vanilla x86_64, instead of AVX2. Appreciate it if someone can work on fixing this. command line: g++ -O3 -fopenmp openmp_wrong_target_isa.cpp Sorry, I couldn't include the preprocessed file as requested - exceeds upload limit. gcc -v output: Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/6/lto-wrapper Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Debian 6.2.0-4' --with-bugurl=file:///usr/share/doc/gcc-6/README.Bugs --enable-languages=c,ada,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-6 --program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new --enable-gnu-unique-object --disable-vtable-verify --enable-libmpx --enable-plugin --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-6-amd64/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-6-amd64 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-6-amd64 --with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --enable-multiarch --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu Thread model: posix gcc version 6.2.0 20160914 (Debian 6.2.0-4)