Eric, adding those flags worked. Thanks! Rob, yes, bug report from libressl matched with what I was getting. Can you please explain what was wrong? I installed the GNU compilers using Homebrew. I realize I should have used “brew link gcc5” or something, but instead, I went to /usr/local/bin and manually created the symlinks (gcc, gfortran, g++, etc) pointing to gcc-5, gfortran-5, etc. Did I miss something? I did not face this issue when I did the same thing (Homebrew gcc + compile MPICH + manual symlinks) on a Macbook. The only difference I see there is that the build is apple-darwin14.4.0. On Oct 30, 2015, at 8:57 AM, Eric A. Borisch <[email protected]<mailto:[email protected]>> wrote: You will need to add '-Wa,-q' for CFLAGS and CXXFLAGS for gcc* on Yosemite and above. This will use the clang assembler. (See man as) <plug>The MacPorts mpich package does this automatically when needed.</plug> - Eric On Fri, Oct 30, 2015 at 10:13 AM, Rob Latham <[email protected]<mailto:[email protected]>> wrote: On 10/28/2015 12:46 PM, Ghosh, Debojyoti wrote: Hi, I am getting a compilation error while trying to compile MPICH on my Mac desktop. I installed the latest GNU compilers using Homebrew. gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/local/Cellar/gcc/5.2.0/libexec/gcc/x86_64-apple-darwin14.5.0/5.2.0/lto-wrapper Target: x86_64-apple-darwin14.5.0 Configured with: ../configure --build=x86_64-apple-darwin14.5.0 --prefix=/usr/local/Cellar/gcc/5.2.0 --libdir=/usr/local/Cellar/gcc/5.2.0/lib/gcc/5 --enable-languages=c,c++,objc,obj-c++,fortran --program-suffix=-5 --with-gmp=/usr/local/opt/gmp --with-mpfr=/usr/local/opt/mpfr --with-mpc=/usr/local/opt/libmpc --with-isl=/usr/local/opt/isl --with-system-zlib --enable-libstdcxx-time=yes --enable-stage1-checking --enable-checking=release --enable-lto --with-build-config=bootstrap-debug --disable-werror --with-pkgversion='Homebrew gcc 5.2.0' --with-bugurl=https://github.com/Homebrew/homebrew/issues --enable-plugin --disable-nls --enable-multilib Thread model: posix gcc version 5.2.0 (Homebrew gcc 5.2.0) We test with gcc-5.2 on our mac build bots, so it's definitely possible. I am getting the following error while compiling MPICH: CC src/mpltrmem.lo /var/folders/qf/q3tp7kgn0gz6qj5_c2nr4qqm001qq3/T//ccyirdXM.s:491:suffix or operands invalid for `movq' /var/folders/qf/q3tp7kgn0gz6qj5_c2nr4qqm001qq3/T//ccyirdXM.s:495:suffix or operands invalid for `movq' make[2]: *** [src/mpltrmem.lo] Error 1 make[1]: *** [all-recursive] Error 1 make: *** [all] Error 2 When the assembler is suspicous ('movq') then it sure seems like there's a toolchain mismatch. Does this bug report from libressl sound like your environment? https://github.com/libressl-portable/portable/issues/121 ==rob -- Rob Latham Mathematics and Computer Science Division Argonne National Lab, IL USA _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss _______________________________________________ discuss mailing list [email protected]<mailto:[email protected]> To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss