The testcase I'll attach is miscompiled on s390x with -m64 -O2 -mtune=z990 or -m64 -O2 -mtune=z9-109. The test function needs a base reg (so %r13 is loaded early and during flow2 the %r13 references actually make it into the assembler). But, during reload a TImode pseudo is reloaded into TI %r12 (and therefore clobbers %r13 too) and the testcase segfaults.
-- Summary: s390x miscompilation due to clobbering literal pool base reg Product: gcc Version: 4.1.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: jakub at gcc dot gnu dot org GCC target triplet: s390x-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27959