https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105402
Bug ID: 105402 Summary: ICE: in emit_swap_insn, at reg-stack.c:837 at -Og with custom target flags Product: gcc Version: 12.0 Status: UNCONFIRMED Keywords: ice-on-valid-code Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: zsojka at seznam dot cz Target Milestone: --- Host: x86_64-pc-linux-gnu Target: x86_64-pc-linux-gnu Created attachment 52888 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52888&action=edit reduced testcase I don't know how much this relates to PR39607; there are no unitialized variables, but there is dead code and undefined behavior (at runtime). Compiler output: $ x86_64-pc-linux-gnu-gcc -Og -mstringop-strategy=libcall -fsanitize=integer-divide-by-zero -mregparm=3 -mtune=eden-x4 -m32 testcase.c testcase.c: In function 'foo': testcase.c:11:5: warning: division by zero [-Wdiv-by-zero] 11 | 0 / 0; | ^ during RTL pass: stack testcase.c:12:1: internal compiler error: in emit_swap_insn, at reg-stack.cc:843 12 | } | ^ 0x7b448f emit_swap_insn /repo/gcc-trunk/gcc/reg-stack.cc:843 0x1355cec move_for_stack_reg /repo/gcc-trunk/gcc/reg-stack.cc:1135 0x1358256 subst_stack_regs /repo/gcc-trunk/gcc/reg-stack.cc:2457 0x13586c9 convert_regs_1 /repo/gcc-trunk/gcc/reg-stack.cc:3091 0x13586c9 convert_regs_2 /repo/gcc-trunk/gcc/reg-stack.cc:3225 0x1359858 convert_regs /repo/gcc-trunk/gcc/reg-stack.cc:3260 0x1359858 reg_to_stack /repo/gcc-trunk/gcc/reg-stack.cc:3385 0x1359858 rest_of_handle_stack_regs /repo/gcc-trunk/gcc/reg-stack.cc:3441 0x1359858 execute /repo/gcc-trunk/gcc/reg-stack.cc:3473 Please submit a full bug report, with preprocessed source (by using -freport-bug). 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-r12-8264-20220426101158-g7d31c678d68-checking-yes-rtl-df-extra-nobootstrap-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/12.0.1/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-r12-8264-20220426101158-g7d31c678d68-checking-yes-rtl-df-extra-nobootstrap-amd64 Thread model: posix Supported LTO compression algorithms: zlib zstd gcc version 12.0.1 20220426 (experimental) (GCC)