some compiler warnings

[hussam]

Seems harmless as the build completes successfully but I thought I'd report them anyway

 

  CC   chat.o
chat.c: In function ‘put_string_in_input_field’:
chat.c:934:12: warning: operation on ‘msg->len’ may be undefined

 CC   pathfinder.o
pathfinder.c: In function ‘pf_destroy_path’:
pathfinder.c:195:27: warning: operation on ‘pf_visited_squares[i]’ may be undefined

CXX  io/elfilewrapper.o
io/elfilewrapper.cpp: In function ‘eternal_lands::el_file* eternal_lands::el_open(const char*)’:
io/elfilewrapper.cpp:32:51: warning: declaration of ‘eternal_lands::el_file* eternal_lands::el_open(const char*)’ with C language linkage
io/elfilewrapper.h:48:20: warning: conflicts with previous declaration ‘el_file* el_open(const char*)’
io/elfilewrapper.cpp: In function ‘eternal_lands::el_file* eternal_lands::el_open_custom(const char*)’:
io/elfilewrapper.cpp:45:58: warning: declaration of ‘eternal_lands::el_file* eternal_lands::el_open_custom(const char*)’ with C language linkage
io/elfilewrapper.h:58:20: warning: conflicts with previous declaration ‘el_file* el_open_custom(const char*)’
io/elfilewrapper.cpp: In function ‘eternal_lands::el_file* eternal_lands::el_open_anywhere(const char*)’:
io/elfilewrapper.cpp:58:60: warning: declaration of ‘eternal_lands::el_file* eternal_lands::el_open_anywhere(const char*)’ with C language linkage
io/elfilewrapper.h:68:20: warning: conflicts with previous declaration ‘el_file* el_open_anywhere(const char*)’
io/elfilewrapper.cpp: In function ‘eternal_lands::el_file* eternal_lands::el_open_no_decompress(const char*)’:
io/elfilewrapper.cpp:71:65: warning: declaration of ‘eternal_lands::el_file* eternal_lands::el_open_no_decompress(const char*)’ with C language linkage
io/elfilewrapper.h:77:20: warning: conflicts with previous declaration ‘el_file* el_open_no_decompress(const char*)’
io/elfilewrapper.cpp: In function ‘int eternal_lands::el_read(eternal_lands::el_file*, int, void*)’:
io/elfilewrapper.cpp:84:62: warning: declaration of ‘int eternal_lands::el_read(eternal_lands::el_file*, int, void*)’ with C language linkage
io/elfilewrapper.h:89:12: warning: conflicts with previous declaration ‘int el_read(el_file*, int, void*)’
io/elfilewrapper.cpp: In function ‘int eternal_lands::el_seek(eternal_lands::el_file*, int, int)’:
io/elfilewrapper.cpp:97:65: warning: declaration of ‘int eternal_lands::el_seek(eternal_lands::el_file*, int, int)’ with C language linkage
io/elfilewrapper.h:103:12: warning: conflicts with previous declaration ‘int el_seek(el_file*, int, int)’
io/elfilewrapper.cpp: In function ‘int eternal_lands::el_tell(eternal_lands::el_file*)’:
io/elfilewrapper.cpp:110:38: warning: declaration of ‘int eternal_lands::el_tell(eternal_lands::el_file*)’ with C language linkage
io/elfilewrapper.h:113:12: warning: conflicts with previous declaration ‘int el_tell(el_file*)’
io/elfilewrapper.cpp: In function ‘int eternal_lands::el_get_size(eternal_lands::el_file*)’:
io/elfilewrapper.cpp:123:42: warning: declaration of ‘int eternal_lands::el_get_size(eternal_lands::el_file*)’ with C language linkage
io/elfilewrapper.h:123:12: warning: conflicts with previous declaration ‘int el_get_size(el_file*)’
io/elfilewrapper.cpp: In function ‘void eternal_lands::el_close(eternal_lands::el_file*)’:
io/elfilewrapper.cpp:136:40: warning: declaration of ‘void eternal_lands::el_close(eternal_lands::el_file*)’ with C language linkage
io/elfilewrapper.h:132:13: warning: conflicts with previous declaration ‘void el_close(el_file*)’
io/elfilewrapper.cpp: In function ‘void* eternal_lands::el_get_pointer(eternal_lands::el_file*)’:
io/elfilewrapper.cpp:146:47: warning: declaration of ‘void* eternal_lands::el_get_pointer(eternal_lands::el_file*)’ with C language linkage
io/elfilewrapper.h:143:14: warning: conflicts with previous declaration ‘void* el_get_pointer(el_file*)’
 CXX  io/elfile.o

[bluap]

I don't get these on gcc version 4.4.3 or 4.4.5. Which compiler/OS combination are you using? I've fixed the first couple as they were reasonably obvious but the elfilewrapper warnings are more tricky.

[korrode]

hussam uses the awesome and bleeding edge Arch Linux which if he sync'd with repo recently will be on gcc 4.5.2

 

i should rly let him answer but couldn't resist plugging mi distro :> ;p

Edited January 19, 2011 by Korrode

[bluap]

hussam uses the awesome and bleeding edge Arch Linux which if he sync'd with repo recently will be on gcc 4.5.2

 

i should rly let him answer but couldn't resist plugging mi distro :> ;p

Well, what a coincidence. I've currently configuring a fresh install of Arch Linux in a virtual machine. This is the first time I've tried it.

[hussam]

hussam uses the awesome and bleeding edge Arch Linux which if he sync'd with repo recently will be on gcc 4.5.2

 

i should rly let him answer but couldn't resist plugging mi distro :> ;p

Well, what a coincidence. I've currently configuring a fresh install of Arch Linux in a virtual machine. This is the first time I've tried it.

You'll love it, bluap. startup daemons are easy to configure in /etc/rc.conf and pacman (the package manager) is very nice

[revi]

I don't get these on gcc version 4.4.3 or 4.4.5. Which compiler/OS combination are you using? I've fixed the first couple as they were reasonably obvious but the elfilewrapper warnings are more tricky.

 

I get those also using GCC 4.5.2 on OpenSuse.

 

Just to check if I'm on the right track:

as I see it, these warnings are caused by the use of namespace eternal_lands, and the use of this code by both C and C++ code:

the elfilewrapper.h header file always declares the functions in the global namespace (necessary, as C doesn't know about namespaces)

the elfilewrapper.c implementation always declares the functions in the eternal_lands namespace, but with C linkage;

 

this means that the functions appear to be in the global namespace in the object file (so linking works as expected),

but for the C++ compiler there are 2 declarations for each function:

the one in the header in global namespace (e.g. el_open(...) )

the one in the .cpp in the eternal_lands namespace (e.g. eternal_lands::el_open(...) )

these two symbols are different, and the compiler can't be sure they refer to the same function => conflict => warning.

 

And you cannot just add a (conditional) 'namespace eternal_lands' to the header either... (compilation errors!)