[Bug target/65837] [arm-linux-gnueabihf] lto1 target specific builtin not available

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65837

--- Comment #6 from rguenther at suse dot de <rguenther at suse dot de> ---
On Wed, 22 Apr 2015, prathamesh3492 at gcc dot gnu.org wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65837
> 
> --- Comment #3 from prathamesh3492 at gcc dot gnu.org ---
> Hi,
> I tried to reproduce the error with a reduced test-case:
> 
> #include "arm_neon.h"
> 
> float32x2_t a, b, c, e;
> 
> int main()
> {
>   e = __builtin_neon_vmls_lanev2sf (a, b, c, 0);
>   return 0;
> }
> 
> arm-linux-gnueabihf-gcc -mfpu=neon test.c -flto test.c -c
> arm-linux-gnueabihf-gcc test.o -flto -o test
> lto1: fatal error: target specific builtin not available
> compilation terminated.
> lto-wrapper: fatal error:
> /home/prathamesh.kulkarni/gnu-toolchain/gcc-chromium-arm-linux-gnueabihf/builds/destdir/x86_64-unknown-linux-gnu/bin/arm-linux-gnueabihf-gcc
> returned 1 exit status
> compilation terminated.
> 
> However passing -mfpu=neon for linking works:
> arm-linux-gnueabihf-gcc -mfpu=neon test.o -flto -o test
> 
> I suppose similar thing must be happening during linking
> libshared_memory_support.so for chromium build ?
> I couldn't see -mfpu=neon in the command line used for linking
> libshared_memory_support.so

What needs to happen is that -mfpu=neon should be enabled for
main() via TARGET_OPTION_NODE streaming.  And switching to main()
the needs to initialize the builtins enabled by -mfpu=neon.

Should be reproducible without LTO with

int __attribute__((target("fpu=neon"))) main() 
{
...
}

and compiling without -mfpu=neon.

Richard.