[Bug bootstrap/100340] Bootstrap fails with Clang 12.0.5 (XCode 12.5)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100340 --- Comment #6 from Iain Sandoe --- (In reply to Richard Biener from comment #5) > Does it work when you use STAGE1_CFLAGS="-O0" (I think clang defaults to > optimizing?). To rule out compare-debug issues also try > --without-build-config The reason for the fail is that the assembler (clang -cc1as) is assembling branch instructions with differing lengths between the debug and non-debug cases. The code is not actually wrong in either case - it simply looks like branch relaxation has been enabled in one case and not the other. However this is not in response to changed command line options (so it is an internal decision in the assembler, probably as a result of detecting either .loc directives or presence/absence of L local labels between branch and its destination.). I am discussing with OSS folks at Apple whether this is an intentional change (i.e to produce better optimised code) or an accidental one. Short-term workarounds: 1. (re-)install xcode 12.4 command line tools and select them for use 2. disable debug comparison in the bootstrap ( --without-build-config )
[Bug bootstrap/100340] Bootstrap fails with Clang 12.0.5 (XCode 12.5)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100340 Richard Biener changed: What|Removed |Added Target||x86_64-apple-darwin Host||x86_64-apple-darwin --- Comment #5 from Richard Biener --- Does it work when you use STAGE1_CFLAGS="-O0" (I think clang defaults to optimizing?). To rule out compare-debug issues also try --without-build-config
[Bug bootstrap/100340] Bootstrap fails with Clang 12.0.5 (XCode 12.5)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100340 --- Comment #4 from Jürgen Reuter --- (In reply to Dominique d'Humieres from comment #3) > Confirmed. Merci, Dominique. Would you actually advise to compile without bootstrap and start using gcc, or wait until the reason for the bootstrap failure is understood and hopefully fixed?
[Bug bootstrap/100340] Bootstrap fails with Clang 12.0.5 (XCode 12.5)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100340 Dominique d'Humieres changed: What|Removed |Added Status|UNCONFIRMED |NEW Ever confirmed|0 |1 Last reconfirmed||2021-04-29 CC||iains at gcc dot gnu.org --- Comment #3 from Dominique d'Humieres --- Confirmed.
[Bug bootstrap/100340] Bootstrap fails with Clang 12.0.5 (XCode 12.5)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100340 --- Comment #2 from Jürgen Reuter --- I just check, with --disable-bootstrap, gcc compiles to the end. Just the checksums of the object files for bootstrap between stage 2 and 3 don't agree.
[Bug bootstrap/100340] Bootstrap fails with Clang 12.0.5 (XCode 12.5)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100340 --- Comment #1 from Jürgen Reuter --- After update to macOS Big Sur 11.3 with XCode 12.5 and Apple Clang clang-1205.0.22.9, bootstrap doesn't work any more: Comparing stages 2 and 3 warning: gcc/cc1obj-checksum.o differs warning: gcc/cc1objplus-checksum.o differs Bootstrap comparison failure! gcc/tree-ssa-operands.o differs gcc/tree-ssanames.o differs [...] lib/libz_a-deflate.o differs zlib/libz_a-gzread.o differs zlib/libz_a-inflate.o differs zlib/libz_a-crc32.o differs zlib/libz_a-inftrees.o differs
