Re: signbit issues

[Orion Poplawski]

On 02/07/2016 01:56 PM, Mike Miller wrote:
> On Fri, Feb 05, 2016 at 16:38:08 -0700, Orion Poplawski wrote:
> > I'm afraid I'm not very experience with automake/autoconf so perhaps I've
> > messed something else up.
> >
> > $ cat configure.ac
> > AC_INIT(test, 1.0, address@hidden)
> > AC_CONFIG_SRCDIR(src/foobar.cpp)
> > AM_INIT_AUTOMAKE
> > AC_PROG_CC
> > gl_EARLY
> > AC_PROG_CXX
> > AC_PROG_RANLIB
> > AC_CONFIG_FILES(lib/Makefile)
> > AC_OUTPUT(Makefile src/Makefile)
> > gl_iNIT
>
> Small but important typo, that should be "gl_INIT".
>
> I made a few more adjustments, the following works for me:
>
>    AC_INIT(test, 1.0, address@hidden)
>    AC_CONFIG_SRCDIR(src/foobar.cpp)
>    AM_INIT_AUTOMAKE(foreign)
>    AC_PROG_CC
>    AC_PROG_CXX
>    AC_PROG_RANLIB
>    gl_EARLY
>    gl_INIT
>    AC_CONFIG_HEADERS(config.h)
>    AC_CONFIG_FILES(Makefile lib/Makefile src/Makefile)
>    AC_OUTPUT

Ah, thank you very much for catching that.  Now with a simple:

#include <config.h>
#include <math.h>
#include <cmath>

int main(int argc,char **argv) {
}

I'm able to reproduce the compile error:

g++ -DHAVE_CONFIG_H -I. -I..  -I../lib   -g -O2 -MT foobar.o -MD -MP -MF 
.deps/foobar.Tpo -c -o foobar.o foobar.cpp
In file included from foobar.cpp:2:0:
../lib/math.h: In function ‘int signbit(float)’:
../lib/math.h:2576:1: error: ‘int signbit(float)’ conflicts with a 
previous declaration
 _GL_MATH_CXX_REAL_FLOATING_DECL_2 (signbit)
 ^
In file included from /usr/include/c++/6.0.0/math.h:36:0,
                 from ../lib/math.h:27,
                 from foobar.cpp:2:
/usr/include/c++/6.0.0/cmath:681:3: note: previous declaration 
‘constexpr bool std::signbit(float)’
   signbit(float __x)
   ^~~~~~~
In file included from foobar.cpp:2:0:
../lib/math.h: In function ‘int signbit(double)’:
../lib/math.h:2576:1: error: ‘int signbit(double)’ conflicts with a 
previous declaration
 _GL_MATH_CXX_REAL_FLOATING_DECL_2 (signbit)
 ^
In file included from /usr/include/c++/6.0.0/math.h:36:0,
                 from ../lib/math.h:27,
                 from foobar.cpp:2:
/usr/include/c++/6.0.0/cmath:685:3: note: previous declaration 
‘constexpr bool std::signbit(double)’
   signbit(double __x)
   ^~~~~~~
In file included from foobar.cpp:2:0:
../lib/math.h: In function ‘int signbit(long double)’:
../lib/math.h:2576:1: error: ‘int signbit(long double)’ conflicts with a 
previous declaration
 _GL_MATH_CXX_REAL_FLOATING_DECL_2 (signbit)
 ^
In file included from /usr/include/c++/6.0.0/math.h:36:0,
                 from ../lib/math.h:27,
                 from foobar.cpp:2:
/usr/include/c++/6.0.0/cmath:689:3: note: previous declaration 
‘constexpr bool std::signbit(long double)’
   signbit(long double __x)
   ^~~~~~~

Although I really don't have any good ideas about how to fix this.


--
Orion Poplawski
Technical Manager                     303-415-9701 x222
NWRA, Boulder/CoRA Office             FAX: 303-415-9702
3380 Mitchell Lane                       address@hidden
Boulder, CO 80301                   http://www.nwra.com