[Bug c/66326] Floating point exception with -mfpmath=387 and -fcilkplus.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66326 --- Comment #3 from Eric ejolson at unr dot edu --- GCC version 5.2 has come around and the bug is still here. In particular, compiling for 32-bit Intel or using -mfpmath=387 in 64-bit leads to immediate floating point exceptions. The fix was to comment out the define RESTORE_X86_FP_STATE at the top of libcilkrts/runtime/config/x86/os-unix-sysdep.c because the code in the restore and save routines is SSE only. Note that changing floating point rounding modes may not function as expected on 32-bit or with -mfpmath=387 set, however, otherwise this simple fix is effective. As already before, more information and this work-around is at https://software.intel.com/en-us/forums/topic/558825
[Bug c/66326] Floating point exception with -mfpmath=387 and -fcilkplus.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66326 --- Comment #1 from Eric ejolson at unr dot edu --- The compilers gcc-5.1 and cilkplus-4_8-branch were bootstrapped using the Debian 4.7.2-5 gcc compiler on Debian Wheezy. Compiling and running the test program yields the following output: $ /usr/local/gcc-5.1/bin/gcc -fcilkplus -Wall \ -mfpmath=387 fpbug.c -o fpbug-gcc510-387 -lcilkrts -lm $ ./fpbug-gcc510-387 Floating point exception $ /usr/local/gcc-5.1/bin/gcc -fcilkplus -Wall \ -mfpmath=sse fpbug.c -o fpbug-gcc510-sse -lcilkrts -lm $ ./fpbug-gcc510-sse f(1)+g(2)=0.850648 $ /usr/local/cilk-4.8/bin/gcc -fcilkplus -Wall \ -mfpmath=387 fpbug.c -o fpbug-cilk48-387 -lcilkrts -lm $ ./fpbug-cilk48-387 f(1)+g(2)=0.850648 $ /usr/local/cilk-4.8/bin/gcc -fcilkplus -Wall \ -mfpmath=sse fpbug.c -o fpbug-cilk48-sse -lcilkrts -lm $ ./fpbug-cilk48-sse f(1)+g(2)=0.850648
[Bug c/66326] Floating point exception with -mfpmath=387 and -fcilkplus.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66326 --- Comment #2 from Eric ejolson at unr dot edu --- Additional information and discussion about this bug may be found on the Intel Cilk Plus developer forum at https://software.intel.com/en-us/forums/topic/558825
