[Bug other/52646] New: Clang LLVM's __attribute__((naked)) for GCC when compiling for x86
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52646 Bug #: 52646 Summary: Clang LLVM's __attribute__((naked)) for GCC when compiling for x86 Classification: Unclassified Product: gcc Version: unknown Status: UNCONFIRMED Severity: enhancement Priority: P3 Component: other AssignedTo: unassig...@gcc.gnu.org ReportedBy: th020...@gmail.com It would be helpful to system developers if GCC had something similar to Clang LLVM's __attribute__((naked)) for x86 targets. There are cases, such as when interfacing with assembly or when handling an interrupt, when the code that precedes and follows a normal function causes problems. GCC already has __attribute__((interrupt)) for multiple targets, but doesn't implement it for x86. Personally, if the feature were to be implemented, I believe naked is more explicit. I'd be glad to do this myself, but I'm not acquainted with GCC at all. What files should I look in to get started?
[Bug other/52646] Clang LLVM's __attribute__((naked)) for GCC when compiling for x86
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52646 --- Comment #2 from Tyler Hardin 2012-03-21 00:44:39 UTC --- While I admit my knowledge of interrupts on ARM, AVR, CR16, Epiphany, M32C, M32R/D, m68k, MeP, MIPS, RL78, RX and Xstormy16 is limited; I don't see why, if GCC supports interrupts on all of them, then it shouldn't have support for others. Is there something special about them?
[Bug other/52646] Clang LLVM's __attribute__((naked)) for GCC when compiling for x86
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52646 --- Comment #4 from Tyler Hardin 2012-03-21 01:07:20 UTC --- If I care enough to implement them for x86, do you believe it would be included in GCC? If not, I won't waste my time with it (while it's worth my time to implement it, it's not worth my time to maintain a fork that has my patch). If you do, then I would really appreciate a hint about where to start. I realize it may be obscure, so I understand if no one has a clue.
[Bug inline-asm/51863] New: invlpg with -masm=intel generates memory operand size error in assembly stage
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.
[Bug inline-asm/51863] invlpg with -masm=intel generates memory operand size error in assembly stage
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51863 --- Comment #1 from Tyler Hardin 2012-01-15 06:05:49 UTC --- Created attachment 26328 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=26328 A source file that generates the error.
[Bug inline-asm/51863] invlpg with -masm=intel generates memory operand size error in assembly stage
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51863
Tyler Hardin changed:
What|Removed |Added
Status|RESOLVED|UNCONFIRMED
Resolution|INVALID |
--- Comment #3 from Tyler Hardin 2012-01-15
08:49:26 UTC ---
(In reply to comment #2)
> I think you should use:
> asm("invlpg %0" :: "r"(pointer_to_page) : "memory");
> Instead.
invlpg only accepts memory operands. But, if I adapt your idea just a little,
it works:
asm("invlpg [%0]" :: "r"(pointer_to_page) : "memory");
It would be nice if it would work without having to trick the compiler (telling
it I'm using a register but actually referencing memory), but it works now,
that's all I care about. Thanks.
> What GCC is doing is correct in that it outputs the byte/word/dword
> correctly for -masm=intel.
But why for -masm=intel and not for -masm=att (the default)?
