Re: signbit(), C++, and Solaris 10

[Bruno Haible]

Hi,

G. Branden Robinson wrote:
> I'm trying to get the forthcoming groff release building on the
> geriatric Solaris 10, something that worked as recently as July 2023.
> 
> I ran into the following problem.
> 
>     In file included from ./src/include/driver.h:25:0,
>                      from src/devices/grodvi/dvi.cpp:25:
>     ./lib/math.h: In function ‘bool signbit(float)’:
>     ./lib/math.h:3281:1: error: ‘bool signbit(float)’ conflicts with a 
> previous declaration
>      _GL_MATH_CXX_REAL_FLOATING_DECL_2 (signbit, signbit, bool)
>      ^
>     In file included from 
> /opt/csw/lib/gcc/sparc-sun-solaris2.10/5.5.0/include-fixed/math.h:23:0,
>                      from ./lib/math.h:46,
>                      from ./src/include/driver.h:25,
>                      from src/devices/grodvi/dvi.cpp:25:
>     /usr/include/iso/math_c99.h:688:14: note: previous declaration ‘bool 
> std::signbit(float)’
>       inline bool signbit(float __X) { return __builtin_signbitf(__X); }

Building a gnulib testdir of module 'signbit', --with-c++-tests,
on Solaris 10 with gcc+g++ works fine.

Therefore: please point me to a tarball that exhibits the problem for you,
so that I can reproduce.

Bruno