https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68285
Bug ID: 68285 Summary: Assembler error on x86_64-linux-gnu: invalid instruction suffix for `movabs' Product: gcc Version: 6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: su at cs dot ucdavis.edu Target Milestone: --- The current gcc trunk generates an assembler error when compiling the following code on x86_64-linux-gnu at -O1 and above in the 64-bit mode (but not in the 32-bit mode). This is a regression from 5.2.x. $ gcc-trunk -v Using built-in specs. COLLECT_GCC=gcc-trunk COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/6.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../gcc-trunk/configure --prefix=/usr/local/gcc-trunk --enable-languages=c,c++ --disable-werror --enable-multilib Thread model: posix gcc version 6.0.0 20151109 (experimental) [trunk revision 230020] (GCC) $ $ gcc-trunk -m64 -O0 small.c $ gcc-trunk -m32 -O1 small.c $ gcc-5.2 -m64 -O1 small.c $ $ gcc-trunk -m64 -O1 small.c /tmp/ccwczUop.s: Assembler messages: /tmp/ccwczUop.s:8: Error: invalid instruction suffix for `movabs' /tmp/ccwczUop.s:18: Error: invalid instruction suffix for `movabs' $ $ cat small.c struct { volatile int f0; } a[4194305]; void fn1 () { a[4194304].f0; } int main () { fn1 (); return 0; }