https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71109
Bug ID: 71109 Summary: gcc ICE at -O3 on valid code on x86_64-linux-gnu in "maybe_record_trace_start" Product: gcc Version: 7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: helloqirun at gmail dot com Target Milestone: --- The following valid code causes an ICE when compiled with the current gcc trunk at only -O3 on x86_64-linux-gnu in 64-bit mode. 32-bit mode works fine. It appears to be a 7 regression. $ gcc-trunk -v Using built-in specs. COLLECT_GCC=gcc-trunk COLLECT_LTO_WRAPPER=/home/absozero/trunk/root-gcc/libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../gcc/configure --prefix=/home/absozero/trunk/root-gcc --enable-languages=c,c++ --disable-werror --enable-multilib Thread model: posix gcc version 7.0.0 20160513 (experimental) [trunk revision 236209] (GCC) $ gcc-trunk -O3 abc.c -c abc.c: In function ‘fn2’: abc.c:26:1: internal compiler error: in maybe_record_trace_start, at dwarf2cfi.c:2284 } ^ 0x827738 maybe_record_trace_start ../../gcc/gcc/dwarf2cfi.c:2284 0x829e30 scan_trace ../../gcc/gcc/dwarf2cfi.c:2462 0x82a66a create_cfi_notes ../../gcc/gcc/dwarf2cfi.c:2616 0x82a66a execute_dwarf2_frame ../../gcc/gcc/dwarf2cfi.c:2974 0x82a66a execute ../../gcc/gcc/dwarf2cfi.c:3454 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <http://gcc.gnu.org/bugs.html> for instructions. $ cat abc.c struct S0 { int f0; int f1; char f2; int f3; char f4; int f5; int f6; int f7; char f8; } a, c; struct S1 { char f0; } e; int *b; int d; void fn1(); void fn2() { for (; d;) { fn1(fn2, a); struct S1 f[3]; int k; for (;; k++) f[k] = e; } } void fn1(int p1, struct S0 p2, struct S1 p3) { p3.f0 = 2; for (; p3.f0; p3.f0--) { struct S0 *g = &a, *h = &c; *h = *g = p2; *b |= 6; if (p2.f0) break; } }