On Mon, 7 Nov 2022 at 19:13, Jakub Jelinek <ja...@redhat.com> wrote: > > On Mon, Nov 07, 2022 at 05:48:42PM +0000, Jonathan Wakely wrote: > > On Mon, 7 Nov 2022 at 16:11, Joseph Myers <jos...@codesourcery.com> wrote: > > > > > > On Wed, 2 Nov 2022, Jakub Jelinek via Gcc-patches wrote: > > > > > > > APIs. So that one can build gcc against older glibc and then compile > > > > user programs on newer glibc, the patch uses weak references unless > > > > gcc is compiled against glibc 2.26+. strfromf128 unfortunately can't > > > > > > This support for older glibc doesn't actually seem to be working, on an > > > older system with glibc 2.19 I'm seeing > > > > > > /scratch/jmyers/fsf/gcc-mainline/libstdc++-v3/src/c++17/floating_to_chars.cc:52:3: > > > error: expected initializer before '__asm' > > > 52 | __asm ("strfromf128"); > > > | ^~~~~ > > > > > > and a series of subsequent errors. > > > > This seems to "fix" it (not sure if it's right though): > > > > #ifndef _GLIBCXX_HAVE_FLOAT128_MATH > > extern "C" _Float128 __strtof128(const char*, char**) > > __attribute__((__weak__)); > > #endif > > extern "C" _Float128 __strtof128(const char*, char**) > > __asm ("strtof128"); > > It is, but floating_from_chars.cc has the same problem, > and I think we can avoid the duplication, like this:
OK for trunk, thanks. > > 2022-11-07 Jakub Jelinek <ja...@redhat.com> > > * src/c++17/floating_from_chars.cc (__strtof128): Put __asm before > __attribute__. > * src/c++17/floating_to_chars.cc (__strfromf128): Likewise. > > --- libstdc++-v3/src/c++17/floating_from_chars.cc.jj 2022-11-07 > 15:15:42.928314819 +0100 > +++ libstdc++-v3/src/c++17/floating_from_chars.cc 2022-11-07 > 20:09:47.267983154 +0100 > @@ -63,10 +63,11 @@ extern "C" __ieee128 __strtoieee128(cons > && defined(__GLIBC_PREREQ) > #define USE_STRTOF128_FOR_FROM_CHARS 1 > extern "C" _Float128 __strtof128(const char*, char**) > + __asm ("strtof128") > #ifndef _GLIBCXX_HAVE_FLOAT128_MATH > __attribute__((__weak__)) > #endif > - __asm ("strtof128"); > + ; > #endif > > #if _GLIBCXX_FLOAT_IS_IEEE_BINARY32 && _GLIBCXX_DOUBLE_IS_IEEE_BINARY64 \ > --- libstdc++-v3/src/c++17/floating_to_chars.cc.jj 2022-11-07 > 15:15:42.929314805 +0100 > +++ libstdc++-v3/src/c++17/floating_to_chars.cc 2022-11-07 20:10:13.189627684 > +0100 > @@ -46,10 +46,11 @@ extern "C" int __sprintfieee128(char*, c > #elif __FLT128_MANT_DIG__ == 113 && __LDBL_MANT_DIG__ != 113 \ > && defined(__GLIBC_PREREQ) > extern "C" int __strfromf128(char*, size_t, const char*, _Float128) > + __asm ("strfromf128") > #ifndef _GLIBCXX_HAVE_FLOAT128_MATH > __attribute__((__weak__)) > #endif > - __asm ("strfromf128"); > + ; > #endif > > // This implementation crucially assumes float/double have the > > > Jakub >