https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63155
--- Comment #35 from Rogério de Souza Moraes <rogerio.souza at gmail dot com> --- Created attachment 44791 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44791&action=edit Small testcase more similar to original environment Hi Richard, this is a new testcase, based on another file in the original environment. It’s quite small (7000 lines, 240 setjmp calls). This code with a little complex but still simplified control structure represents state machine implementation, which is very widely used by our customers. Another new factor is the nested setjmp calls. Of course, original testcase is more complex and takes even more time with more difference. You can run it using the following commands: time gcc -DGCC -DLINUX_C -D_GLIBCXX_USE_CXX11_ABI=0 -m32 -m32 -w -c -O0 -pedantic -fwrapv -mstackrealign -mpreferred-stack-boundary=4 gcc_2nd_synth_pure_c_item.c -o gcc_2nd_synth_pure_c_item.o time gcc -DGCC -DLINUX_C -D_GLIBCXX_USE_CXX11_ABI=0 -m32 -m32 -w -c -O -pedantic -fwrapv -mstackrealign -mpreferred-stack-boundary=4 gcc_2nd_synth_pure_c_item.c -o gcc_2nd_synth_pure_c_item.o Results : GCC: 4.8.5 (From RHEL 7.5) real 0m0.349s user 0m0.255s sys 0m0.083s real 0m0.193s user 0m0.163s sys 0m0.023s GCC: 6.3.0 (GCC 6.3.0 with Revision 264523 backported and applied to it) real 0m32.235s user 0m30.486s sys 0m1.622s real 3m34.203s user 3m33.726s sys 0m0.292s The performance difference is relevant in this test. Regards, -- Rogerio
