Re: undefined reference to `_program_name' (error.c)

[Bruno Haible]

Hello,

Daniel Martin wrote:
> When I finally come to linking my program, (again this is when
> cross-compiling to mingw32) I'm getting the following error:
> 
> i386-mingw32-g++ -I/home/dan/usr/cross/i386-mingw32/include -ggdb3 -Wall
> -I/home/dan/usr/cross/i386-mingw32/include -s -o pendulum.exe
> pendulum-arguments.o pendulum-interface.o pendulum-maths.o
> pendulum-main.o pendulum-pendulum.o pendulum-simulation.o
> pendulum-vec3.o  -L/home/dan/usr/cross/i386-mingw32/lib
> guis/.libs/libguis.a -L/home/dan/usr/cross/i386-mingw32//lib
> -lwx_base-2.8 -lwx_base_net-2.8 -lwx_msw_core-2.8 -lwx_msw_adv-2.8
> -lwx_msw_gl-2.8
> systems/.libs/libsystems.a ../gnulib/src/.libs/libgnu.a  
> ../gnulib/src/.libs/libgnu.a(error.o):error.c:(.text+0xe1): undefined
> reference to `_program_name'
> ../gnulib/src/.libs/libgnu.a(error.o):error.c:(.text+0x1a1): undefined
> reference to `_program_name'
> 
> This can be worked around by replacing line 98 or error.c:
> 
> extern char *program_name;
> 
> with:
> 
> char* program_name = "";
> 
> But I'm pretty sure that's not the correct way to do it!
> 
> Where is program_name supposed to be set?

The program_name variable is supposed to be defined either in the 'progname'
module or in your main program. And it should be filled when your main
program starts. See also the gnulib doc at
http://www.gnu.org/software/gnulib/manual/html_node/error-and-progname.html

Bruno