x86: Fix x86_64 build failure with -Os (BZ 33367)
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Description |
| redhat-pt-bot/TryBot-apply_patch |
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Patch applied to master at the time it was sent
|
| redhat-pt-bot/TryBot-32bit |
success
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Build for i686
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Commit Message
The 13cfd77bf5 change broke the b5d88fa6c3 fix by removing the symbol
to __symbol redirections. Although it works for -O2 with both gcc
and clang, with -Os without the redirection, the libcall might still
be issued.
This patch reinstates the b5d88fa6c3 fix, with a modification that
allows each ifunc variant to control which trunc to issue. This is
required for clang, which defines HAVE_X86_INLINE_TRUNC to 1 (meaning
that trunc will always be lowered to the instruction on -Os).
Checked on x86_64-linux-gnu with -O2 and -Os with gcc-15 and clang-18.
---
sysdeps/ieee754/dbl-64/s_modf.c | 5 ++++-
sysdeps/ieee754/flt-32/s_modff.c | 5 ++++-
sysdeps/x86_64/fpu/multiarch/s_modf-avx.c | 1 +
sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c | 1 +
sysdeps/x86_64/fpu/multiarch/s_modff-avx.c | 1 +
sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c | 1 +
6 files changed, 12 insertions(+), 2 deletions(-)
Comments
On 12/23/25 12:30 PM, Adhemerval Zanella wrote:
> The 13cfd77bf5 change broke the b5d88fa6c3 fix by removing the symbol
> to __symbol redirections. Although it works for -O2 with both gcc
> and clang, with -Os without the redirection, the libcall might still
> be issued.
>
> This patch reinstates the b5d88fa6c3 fix, with a modification that
> allows each ifunc variant to control which trunc to issue. This is
> required for clang, which defines HAVE_X86_INLINE_TRUNC to 1 (meaning
> that trunc will always be lowered to the instruction on -Os).
>
> Checked on x86_64-linux-gnu with -O2 and -Os with gcc-15 and clang-18.
This looks perfectly fine to me and we want -Os working.
Pre-commit CI is clean so 32-bit works.
Please push this as the fix.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
> ---
> sysdeps/ieee754/dbl-64/s_modf.c | 5 ++++-
> sysdeps/ieee754/flt-32/s_modff.c | 5 ++++-
> sysdeps/x86_64/fpu/multiarch/s_modf-avx.c | 1 +
> sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c | 1 +
> sysdeps/x86_64/fpu/multiarch/s_modff-avx.c | 1 +
> sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c | 1 +
> 6 files changed, 12 insertions(+), 2 deletions(-)
>
> diff --git a/sysdeps/ieee754/dbl-64/s_modf.c b/sysdeps/ieee754/dbl-64/s_modf.c
> index 77e0226be9..2462529db5 100644
> --- a/sysdeps/ieee754/dbl-64/s_modf.c
> +++ b/sysdeps/ieee754/dbl-64/s_modf.c
> @@ -25,12 +25,15 @@ __modf (double x, double *iptr)
> {
> uint64_t t = asuint64 (x);
> #if USE_TRUNC_BUILTIN
> +# ifndef TRUNC
> +# define TRUNC trunc
> +# endif
> if (is_inf (t))
> {
> *iptr = x;
> return copysign (0.0, x);
> }
> - *iptr = trunc (x);
> + *iptr = TRUNC (x);
> return copysign (x - *iptr, x);
> #else
> int e = get_exponent (t);
> diff --git a/sysdeps/ieee754/flt-32/s_modff.c b/sysdeps/ieee754/flt-32/s_modff.c
> index b5dac7521d..4ae14832c4 100644
> --- a/sysdeps/ieee754/flt-32/s_modff.c
> +++ b/sysdeps/ieee754/flt-32/s_modff.c
> @@ -25,12 +25,15 @@ __modff (float x, float *iptr)
> {
> uint32_t t = asuint (x);
> #if USE_TRUNCF_BUILTIN
> +# ifndef TRUNCF
> +# define TRUNCF truncf
> +# endif
> if (is_inf (t))
> {
> *iptr = x;
> return copysignf (0.0, x);
> }
> - *iptr = truncf (x);
> + *iptr = TRUNCF (x);
> return copysignf (x - *iptr, x);
> #else
> int e = get_exponent (t);
> diff --git a/sysdeps/x86_64/fpu/multiarch/s_modf-avx.c b/sysdeps/x86_64/fpu/multiarch/s_modf-avx.c
> index 9b8b951a97..76e7896277 100644
> --- a/sysdeps/x86_64/fpu/multiarch/s_modf-avx.c
> +++ b/sysdeps/x86_64/fpu/multiarch/s_modf-avx.c
> @@ -1,2 +1,3 @@
> #define __modf __modf_avx
> +#define TRUNC __trunc
> #include <sysdeps/ieee754/dbl-64/s_modf.c>
> diff --git a/sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c b/sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c
> index 1f77386336..49fa4f0b97 100644
> --- a/sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c
> +++ b/sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c
> @@ -1,2 +1,3 @@
> #define __modf __modf_sse41
> +#define TRUNC __trunc
> #include <sysdeps/ieee754/dbl-64/s_modf.c>
> diff --git a/sysdeps/x86_64/fpu/multiarch/s_modff-avx.c b/sysdeps/x86_64/fpu/multiarch/s_modff-avx.c
> index 488f93700c..3b00c364b1 100644
> --- a/sysdeps/x86_64/fpu/multiarch/s_modff-avx.c
> +++ b/sysdeps/x86_64/fpu/multiarch/s_modff-avx.c
> @@ -1,2 +1,3 @@
> #define __modff __modff_avx
> +#define TRUNCF __truncf
> #include <sysdeps/ieee754/flt-32/s_modff.c>
> diff --git a/sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c b/sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c
> index 8e49970ffc..58d46582bd 100644
> --- a/sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c
> +++ b/sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c
> @@ -1,2 +1,3 @@
> #define __modff __modff_sse41
> +#define TRUNCF __truncf
> #include <sysdeps/ieee754/flt-32/s_modff.c>
Am Montag, 5. Januar 2026, 15:13:31 Mitteleuropäische Normalzeit schrieb Carlos O'Donell:
> On 12/23/25 12:30 PM, Adhemerval Zanella wrote:
> > The 13cfd77bf5 change broke the b5d88fa6c3 fix by removing the symbol
> > to __symbol redirections. Although it works for -O2 with both gcc
> > and clang, with -Os without the redirection, the libcall might still
> > be issued.
> >
> > This patch reinstates the b5d88fa6c3 fix, with a modification that
> > allows each ifunc variant to control which trunc to issue. This is
> > required for clang, which defines HAVE_X86_INLINE_TRUNC to 1 (meaning
> > that trunc will always be lowered to the instruction on -Os).
> >
> > Checked on x86_64-linux-gnu with -O2 and -Os with gcc-15 and clang-18.
>
> This looks perfectly fine to me and we want -Os working.
>
> Pre-commit CI is clean so 32-bit works.
>
> Please push this as the fix.
Please do.
>
> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
>
> > ---
> > sysdeps/ieee754/dbl-64/s_modf.c | 5 ++++-
> > sysdeps/ieee754/flt-32/s_modff.c | 5 ++++-
> > sysdeps/x86_64/fpu/multiarch/s_modf-avx.c | 1 +
> > sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c | 1 +
> > sysdeps/x86_64/fpu/multiarch/s_modff-avx.c | 1 +
> > sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c | 1 +
> > 6 files changed, 12 insertions(+), 2 deletions(-)
> >
> > diff --git a/sysdeps/ieee754/dbl-64/s_modf.c b/sysdeps/ieee754/dbl-64/s_modf.c
> > index 77e0226be9..2462529db5 100644
> > --- a/sysdeps/ieee754/dbl-64/s_modf.c
> > +++ b/sysdeps/ieee754/dbl-64/s_modf.c
> > @@ -25,12 +25,15 @@ __modf (double x, double *iptr)
> > {
> > uint64_t t = asuint64 (x);
> > #if USE_TRUNC_BUILTIN
> > +# ifndef TRUNC
> > +# define TRUNC trunc
> > +# endif
> > if (is_inf (t))
> > {
> > *iptr = x;
> > return copysign (0.0, x);
> > }
> > - *iptr = trunc (x);
> > + *iptr = TRUNC (x);
> > return copysign (x - *iptr, x);
> > #else
> > int e = get_exponent (t);
> > diff --git a/sysdeps/ieee754/flt-32/s_modff.c b/sysdeps/ieee754/flt-32/s_modff.c
> > index b5dac7521d..4ae14832c4 100644
> > --- a/sysdeps/ieee754/flt-32/s_modff.c
> > +++ b/sysdeps/ieee754/flt-32/s_modff.c
> > @@ -25,12 +25,15 @@ __modff (float x, float *iptr)
> > {
> > uint32_t t = asuint (x);
> > #if USE_TRUNCF_BUILTIN
> > +# ifndef TRUNCF
> > +# define TRUNCF truncf
> > +# endif
> > if (is_inf (t))
> > {
> > *iptr = x;
> > return copysignf (0.0, x);
> > }
> > - *iptr = truncf (x);
> > + *iptr = TRUNCF (x);
> > return copysignf (x - *iptr, x);
> > #else
> > int e = get_exponent (t);
> > diff --git a/sysdeps/x86_64/fpu/multiarch/s_modf-avx.c b/sysdeps/x86_64/fpu/multiarch/s_modf-avx.c
> > index 9b8b951a97..76e7896277 100644
> > --- a/sysdeps/x86_64/fpu/multiarch/s_modf-avx.c
> > +++ b/sysdeps/x86_64/fpu/multiarch/s_modf-avx.c
> > @@ -1,2 +1,3 @@
> > #define __modf __modf_avx
> > +#define TRUNC __trunc
> > #include <sysdeps/ieee754/dbl-64/s_modf.c>
> > diff --git a/sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c b/sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c
> > index 1f77386336..49fa4f0b97 100644
> > --- a/sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c
> > +++ b/sysdeps/x86_64/fpu/multiarch/s_modf-sse4_1.c
> > @@ -1,2 +1,3 @@
> > #define __modf __modf_sse41
> > +#define TRUNC __trunc
> > #include <sysdeps/ieee754/dbl-64/s_modf.c>
> > diff --git a/sysdeps/x86_64/fpu/multiarch/s_modff-avx.c b/sysdeps/x86_64/fpu/multiarch/s_modff-avx.c
> > index 488f93700c..3b00c364b1 100644
> > --- a/sysdeps/x86_64/fpu/multiarch/s_modff-avx.c
> > +++ b/sysdeps/x86_64/fpu/multiarch/s_modff-avx.c
> > @@ -1,2 +1,3 @@
> > #define __modff __modff_avx
> > +#define TRUNCF __truncf
> > #include <sysdeps/ieee754/flt-32/s_modff.c>
> > diff --git a/sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c b/sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c
> > index 8e49970ffc..58d46582bd 100644
> > --- a/sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c
> > +++ b/sysdeps/x86_64/fpu/multiarch/s_modff-sse4_1.c
> > @@ -1,2 +1,3 @@
> > #define __modff __modff_sse41
> > +#define TRUNCF __truncf
> > #include <sysdeps/ieee754/flt-32/s_modff.c>
>
>
>
@@ -25,12 +25,15 @@ __modf (double x, double *iptr)
{
uint64_t t = asuint64 (x);
#if USE_TRUNC_BUILTIN
+# ifndef TRUNC
+# define TRUNC trunc
+# endif
if (is_inf (t))
{
*iptr = x;
return copysign (0.0, x);
}
- *iptr = trunc (x);
+ *iptr = TRUNC (x);
return copysign (x - *iptr, x);
#else
int e = get_exponent (t);
@@ -25,12 +25,15 @@ __modff (float x, float *iptr)
{
uint32_t t = asuint (x);
#if USE_TRUNCF_BUILTIN
+# ifndef TRUNCF
+# define TRUNCF truncf
+# endif
if (is_inf (t))
{
*iptr = x;
return copysignf (0.0, x);
}
- *iptr = truncf (x);
+ *iptr = TRUNCF (x);
return copysignf (x - *iptr, x);
#else
int e = get_exponent (t);
@@ -1,2 +1,3 @@
#define __modf __modf_avx
+#define TRUNC __trunc
#include <sysdeps/ieee754/dbl-64/s_modf.c>
@@ -1,2 +1,3 @@
#define __modf __modf_sse41
+#define TRUNC __trunc
#include <sysdeps/ieee754/dbl-64/s_modf.c>
@@ -1,2 +1,3 @@
#define __modff __modff_avx
+#define TRUNCF __truncf
#include <sysdeps/ieee754/flt-32/s_modff.c>
@@ -1,2 +1,3 @@
#define __modff __modff_sse41
+#define TRUNCF __truncf
#include <sysdeps/ieee754/flt-32/s_modff.c>