https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86891
Bug ID: 86891 Summary: [9 Regression] wrong code with -O -frerun-cse-after-loop -fno-tree-dominator-opts -fno-tree-fre Product: gcc Version: 9.0 Status: UNCONFIRMED Keywords: wrong-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 Target: aarch64-unknown-linux-gnu Created attachment 44520 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44520&action=edit reduced testcase Output: $ aarch64-unknown-linux-gnu-gcc -O -frerun-cse-after-loop -fno-tree-dominator-opts -fno-tree-fre testcase.c -static $ ./a.out qemu: uncaught target signal 6 (Aborted) - core dumped Aborted $ aarch64-unknown-linux-gnu-gcc -v Using built-in specs. COLLECT_GCC=/repo/gcc-trunk/binary-latest-aarch64/bin/aarch64-unknown-linux-gnu-gcc COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-263387-checking-yes-rtl-df-extra-aarch64/bin/../libexec/gcc/aarch64-unknown-linux-gnu/9.0.0/lto-wrapper Target: aarch64-unknown-linux-gnu Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++ --enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra --with-cloog --with-ppl --with-isl --with-sysroot=/usr/aarch64-unknown-linux-gnu --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=aarch64-unknown-linux-gnu --with-ld=/usr/bin/aarch64-unknown-linux-gnu-ld --with-as=/usr/bin/aarch64-unknown-linux-gnu-as --disable-libstdcxx-pch --prefix=/repo/gcc-trunk//binary-trunk-263387-checking-yes-rtl-df-extra-aarch64 Thread model: posix gcc version 9.0.0 20180808 (experimental) (GCC) The generated code: main: stp x29, x30, [sp, -32]! //,,, mov x29, sp //, // testcase.c:11: u32 d = 7; mov w0, 7 // tmp106, str w0, [sp, 28] // tmp106, d // testcase.c:12: b = __builtin_sub_overflow_p ((u16) - d, (u128) ~ (u8) d, a); adrp x0, b // tmp126, strb wzr, [x0, #:lo12:b] //, b // testcase.c:16: __builtin_abort(); bl abort // just simply calls abort()