Message ID | 20200326123841.134068-1-courbet@google.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | x86: Alias memset to __builtin_memset. | expand |
Context | Check | Description |
---|---|---|
snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch powerpc/merge (c6624071c338732402e8c726df6a4074473eaa0e) |
snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch powerpc/next (7074695ac6fb965d478f373b95bc5c636e9f21b0) |
snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch linus/master (9420e8ade4353a6710908ffafa23ecaf1caa0123) |
snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch powerpc/fixes (1d0c32ec3b860a32df593a22bad0d1dbc5546a59) |
snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch linux-next (89295c59c1f063b533d071ca49d0fa0c0783ca6f) |
snowpatch_ozlabs/apply_patch | fail | Failed to apply to any branch |
Clement Courbet <courbet@google.com> writes: > I discussed with the original authors who added freestanding to our > build. It turns out that it was added globally but this was just to > to workaround powerpc not compiling under clang, but they felt the > fix was appropriate globally. > > Now Nick has dug up https://lkml.org/lkml/2019/8/29/1300, which > advises against freestanding. Also, I've did some research and > discovered that the original reason for using freestanding for > powerpc has been fixed here: > https://lore.kernel.org/linuxppc-dev/20191119045712.39633-3-natechancellor@gmail.com/ > > I'm going to remove -ffreestanding from downstream, so we don't really need > this anymore, sorry for waisting people's time. > > I wonder if the freestanding fix from the aforementioned patch is really needed > though. I think that clang is actually right to point out the issue. > I don't see any reason why setjmp()/longjmp() are declared as taking longs > rather than ints. The implementation looks like it only ever propagates the > value (in longjmp) or sets it to 1 (in setjmp), and we only ever call longjmp > with integer parameters. But I'm not a PowerPC expert, so I might > be misreading the code. > > > So it seems that we could just remove freestanding altogether and rewrite the > code to: > > diff --git a/arch/powerpc/include/asm/setjmp.h b/arch/powerpc/include/asm/setjmp.h > index 279d03a1eec6..7941ae68fe21 100644 > --- a/arch/powerpc/include/asm/setjmp.h > +++ b/arch/powerpc/include/asm/setjmp.h > @@ -12,7 +12,9 @@ > > #define JMP_BUF_LEN 23 > -extern long setjmp(long *); > -extern void longjmp(long *, long); > +typedef long * jmp_buf; > + > +extern int setjmp(jmp_buf); > +extern void longjmp(jmp_buf, int); > > I'm happy to send a patch for this, and get rid of more -ffreestanding. > Opinions ? If it works then it looks like a much better fix than using -ffreestanding. Please submit a patch with a change log etc. and I'd be happy to merge it. cheers
Hi! On Thu, Mar 26, 2020 at 01:38:39PM +0100, Clement Courbet wrote: > --- a/arch/powerpc/include/asm/setjmp.h > +++ b/arch/powerpc/include/asm/setjmp.h > @@ -12,7 +12,9 @@ > > #define JMP_BUF_LEN 23 > -extern long setjmp(long *); > -extern void longjmp(long *, long); > +typedef long * jmp_buf; > + > +extern int setjmp(jmp_buf); > +extern void longjmp(jmp_buf, int); > > I'm happy to send a patch for this, and get rid of more -ffreestanding. > Opinions ? Pedantically, jmp_buf should be an array type. But, this will probably work fine, and it certainly is better than what we had before. You could do typedef long jmp_buf[JMP_BUF_LEN]; perhaps? Thanks, Segher
diff --git a/arch/powerpc/include/asm/setjmp.h b/arch/powerpc/include/asm/setjmp.h index 279d03a1eec6..7941ae68fe21 100644 --- a/arch/powerpc/include/asm/setjmp.h +++ b/arch/powerpc/include/asm/setjmp.h @@ -12,7 +12,9 @@ #define JMP_BUF_LEN 23 -extern long setjmp(long *); -extern void longjmp(long *, long); +typedef long * jmp_buf; + +extern int setjmp(jmp_buf); +extern void longjmp(jmp_buf, int); I'm happy to send a patch for this, and get rid of more -ffreestanding. Opinions ?