[PATCH] math: Fix `unknown type name '__float128'` for clang 3.4 to 3.8.1 (bug 32694)

[H.J. Lu]

On Sun, Feb 23, 2025 at 11:35 AM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> On Sat, Feb 22, 2025 at 10:56 PM koraynilay <koray.fra@gmail.com> wrote:
> >
> > When compiling a program that includes <bits/floatn.h> using a clang version
> > between 3.4 (included) and 3.8.1 (included), clang will fail with `unknown type
> > name '__float128'; did you mean '__cfloat128'?`. This changes fixes the clang
> > prerequirements macro call in floatn.h to check for clang 3.9 instead of 3.4,
> > since support for __float128 was actually enabled in 3.9 (see commit 50f29e0
> > of the llvm-project on github)
> >
> > Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
> > Signed-off-by: koraynilay <koray.fra@gmail.com>
> > ---
> >  sysdeps/x86/bits/floatn.h | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/sysdeps/x86/bits/floatn.h b/sysdeps/x86/bits/floatn.h
> > index adc7ed2e9e..4674165bd7 100644
> > --- a/sysdeps/x86/bits/floatn.h
> > +++ b/sysdeps/x86/bits/floatn.h
> > @@ -31,7 +31,7 @@
> >  #if (defined __x86_64__                                                        \
> >       ? __GNUC_PREREQ (4, 3)                                            \
> >       : (defined __GNU__ ? __GNUC_PREREQ (4, 5) : __GNUC_PREREQ (4, 4))) \
> > -    || (__glibc_clang_prereq (3, 4)                                    \
> > +    || (__glibc_clang_prereq (3, 9)                                    \
> >         && (!defined __INTEL_LLVM_COMPILER                              \
> >             || !defined SYCL_LANGUAGE_VERSION))
> >  # define __HAVE_FLOAT128 1
> > @@ -93,7 +93,7 @@ typedef _Complex float __cfloat128 __attribute__ ((__mode__ (__TC__)));
> >  /* The type _Float128 exists only since GCC 7.0.  */
> >  #  if !__GNUC_PREREQ (7, 0) \
> >        || (defined __cplusplus && !__GNUC_PREREQ (13, 0)) \
> > -      || __glibc_clang_prereq (3, 4)
> > +      || __glibc_clang_prereq (3, 9)
> >  typedef __float128 _Float128;
> >  #  endif
> >
> > --
> > 2.48.1
> >
>
> LGTM.
>
> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
>
> I will push it for you.
>
> Thanks.
>

I am backporting it to 2.41 branch.


-- 
H.J.