In my program I use recursive quick-sort, which is apparently miscompiled by my gcc (Fedora 8, x86_64), when I use -O3 or -O2 -finline-functions. With these options, the data get out of the qsort routine only partially sorted. With -O2 it is OK, and when I add a debugging printf() at the end of the qsort routine (thus disabling the tail-call recursion), it also works (even with -O3 or -O2 -finline-functions).
The test program is at http://www.fi.muni.cz/~kas/data/sorttest.c - try to compile it and run on 64-bit x86_64 system (it is non-portable, but it is a design decision) with -O2 and with -O3. Then uncomment the debugging code near the end of the file, and try it again. -- Summary: -finline-functions miscompiles tail recursion Product: gcc Version: 4.1.2 Status: UNCONFIRMED Severity: normal Priority: P3 Component: regression AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: kas at fi dot muni dot cz GCC build triplet: x86_64-redhat-linux GCC host triplet: x86_64-redhat-linux GCC target triplet: x86_64-redhat-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36082
