Porting gcc :SSE2 problems (invalid opcode): How to disable?

[Haoud]

Hello every one,
I'm ported GCC to my OS with my toolchain i386-haoudos. GCC seems to work correctly( i can use gcc --version in my os).But when i try to compile a file, cc1 throws an invalid opcode because it try to use sse2 instructions.My OS doesn't support sse2, only i387 fpu. How i can disable sse2 instruction for all gcc code?
The invalide opcode is in libcpp/lex.c/search-line-sse2
If you need more informations, don't hesitate to ask me.
Thank you

Sorry for my english but i'm french

[Korona]

Supporting SSE in your OS probably requires less SLoC than your post. Instead of figuring out how to disable SSE in gcc (and all of its libraries) just enable SSE.

[Haoud]

OK. How i can enable SSE and support them (especially for the scheduler) ?

[Mikaku]

I was also porting (now already successfully ported) GCC and Binutils to my OS, and I had _exactly_ the same problem, it took me some weeks to fix it.

Indeed the problem is in libcpp/lex.c file, and I solved it just including an exception for my OS (fiwix) in the line 277. I'm using GCC v4.7.1 so if you are using a different version the line number might vary.

Original line:

Code: Select all

#if (GCC_VERSION >= 4005) && (defined(__i386__) || defined(__x86_64__)) && !(defined(__sun__) && defined(__svr4__))

Patched line which includes my OS:

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#if (GCC_VERSION >= 4005) && (defined(__i386__) || defined(__x86_64__)) && !(defined(__sun__) && defined(__svr4__)) && !defined(__fiwix__)

So now, ported GCC v4.7.1 is able to compile natively in my OS and produce pure i386 executables:

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$ gcc -v
Using built-in specs.
COLLECT_GCC=./gcc
COLLECT_LTO_WRAPPER=./../libexec/gcc/i386-fiwix/4.7.1/lto-wrapper
Target: i386-fiwix
Configured with: ../gcc-4.7.1/configure --host=i386-fiwix --target=i386-fiwix --prefix=/usr --with-arch=i386 -with-buid-sysroot=/home/mikaku/fiwix/sysroot --with-sysroot=/ --with-gmp=/home/mikaku/fiwix/sysroot --with-mpfr=/home/mikaku/fiwix/sysroot --with-mpc=/home/mikaku/fiwix/sysroot --enable-languages=c,c++ --disable-lto --disable-shared --disable-multilib --with-newlib --disable-nls --disable-werror
Thread model: single
gcc version 4.7.1 (GCC) 

I hope that helped you.

[Haoud]

Yes, it's work !! (But i have an another problem ).
Thank you very much