https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88535
Bug ID: 88535 Summary: sparcv9 gcc 7 causes comparison failure in sparc gcc 8 dwarf2out.o Product: gcc Version: 7.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: ro at gcc dot gnu.org CC: ebotcazou at gcc dot gnu.org Target Milestone: --- Host: sparc-sun-solaris2.11 Target: sparc-sun-solaris2.11 Build: sparcv9-sun-solaris2.11 I've gotten a report that building gcc 8.2.0 on Solaris 11.4/SPARC with the bundled gcc 7.3.0 failed with a comparison failure: Comparing stages 2 and 3 Bootstrap comparison failure! gcc/dwarf2out.o differs make[2]: *** [Makefile:22905: compare] Error 1 Since I'd never seen the like of that before, it took me quite some time to reproduce. In the end, it turned out that gcc 7.4.0 configured with --with-as=/usr/gnu/bin/as --with-gnu-as --with-ld=/usr/bin/ld --without-gnu-ld --enable-languages=c,c++ sparcv9-sun-solaris2.11 (i.e. 64-bit default) causes the failure, while the same gcc 7.4.0 configured with --with-as=/usr/gnu/bin/as --with-gnu-as --with-ld=/usr/bin/ld --without-gnu-ld --enable-languages=c,c++ (i.e. 32-bit default) does not. gcc 8.2.0 was configured with --with-as=/usr/gnu/bin/as --with-gnu-as --with-ld=/usr/bin/ld --without-gnu-ld --enable-languages=c,c++ in both cases. There are considerable codegen differences in dwarf2out.c:output_file_names. I haven't yet tried to reduce the testcase or try something similar on mainline, but certainly can if that's helpful.