http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51863
Bug #: 51863 Summary: invlpg with -masm=intel generates memory operand size error in assembly stage Classification: Unclassified Product: gcc Version: 4.6.1 Status: UNCONFIRMED Severity: minor Priority: P3 Component: inline-asm AssignedTo: unassig...@gcc.gnu.org ReportedBy: th020...@gmail.com The expected behavior would be to generate code analogous to that of the default -masm=att, which uses no size prefixes to address the memory operand of invlpg. The actual behavior is that -masm=intel causes GCC to emit code that uses a size prefix (like dword, byte, etc.) which causes an error in GAS when the code is assembled. The command that generates the error is: gcc -masm=intel main.c The same command without -masm=intel works. Output of "gcc -v" Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/lib/gcc/i686-linux-gnu/4.6.1/lto-wrapper Target: i686-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.6.1-9ubuntu3' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++,go --prefix=/usr --program-suffix=-4.6 --enable-shared --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.6 --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin --enable-objc-gc --enable-targets=all --disable-werror --with-arch-32=i686 --with-tune=generic --enable-checking=release --build=i686-linux-gnu --host=i686-linux-gnu --target=i686-linux-gnu Thread model: posix gcc version 4.6.1 (Ubuntu/Linaro 4.6.1-9ubuntu3) The system type is Linux Mint 12, but I've found the same bug in i686-elf for GCC 4.6.2.