https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102141
Bug ID: 102141 Summary: [12 Regression] ICE: verify_ssa failed during GIMPLE pass: bswap at -O2 Product: gcc Version: 12.0 Status: UNCONFIRMED Keywords: ice-on-valid-code Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: zsojka at seznam dot cz Target Milestone: --- Host: x86_64-pc-linux-gnu Created attachment 51386 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=51386&action=edit reduced testcase Compiler output: $ x86_64-pc-linux-gnu-gcc -O2 testcase.c testcase.c: In function 'foo': testcase.c:4:1: error: definition in block 2 follows the use 4 | foo (unsigned long x) | ^~~ for SSA_NAME: bswapdst_14 in statement: _15 = (unsigned int) bswapdst_14; during GIMPLE pass: bswap testcase.c:4:1: internal compiler error: verify_ssa failed 0x14f5bb1 verify_ssa(bool, bool) /repo/gcc-trunk/gcc/tree-ssa.c:1214 0x11b7d85 execute_function_todo /repo/gcc-trunk/gcc/passes.c:2049 0x11b8af3 do_per_function /repo/gcc-trunk/gcc/passes.c:1687 0x11b8af3 execute_todo /repo/gcc-trunk/gcc/passes.c:2096 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <https://gcc.gnu.org/bugs/> for instructions. $ x86_64-pc-linux-gnu-gcc -v Using built-in specs. COLLECT_GCC=/repo/gcc-trunk/binary-latest-amd64/bin/x86_64-pc-linux-gnu-gcc COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-r12-3244-20210831062827-gaba800615e1-checking-yes-rtl-df-extra-nobootstrap-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/12.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++ --enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra --disable-bootstrap --with-cloog --with-ppl --with-isl --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=x86_64-pc-linux-gnu --with-ld=/usr/bin/x86_64-pc-linux-gnu-ld --with-as=/usr/bin/x86_64-pc-linux-gnu-as --disable-libstdcxx-pch --prefix=/repo/gcc-trunk//binary-trunk-r12-3244-20210831062827-gaba800615e1-checking-yes-rtl-df-extra-nobootstrap-amd64 Thread model: posix Supported LTO compression algorithms: zlib zstd gcc version 12.0.0 20210831 (experimental) (GCC)