I haven't programmed in a long while, and am having trouble with a compiler warning. I'm linking to a shared library using clang and am getting the following warning:
warning: implicit declaration of function
'function_name' is invalid in C99
[-Wimplicit-function-declaration]
I have the file included above the function that calls it, so the only thing I can think of that might be causing it, is the function declarations in the shared library's include files, are all declared in the following form:
LIBNAME_API void set_window_title(const char *title);
I think I had this problem when I used Visual Studio a long time ago. I think I set a compiler setting that gave it the name of of the LIBNAME_API, but I can't remember it. How can I fix this in gcc or clang on Linux/Unix?
warning: implicit declaration of function
'function_name' is invalid in C99
[-Wimplicit-function-declaration]
I have the file included above the function that calls it, so the only thing I can think of that might be causing it, is the function declarations in the shared library's include files, are all declared in the following form:
LIBNAME_API void set_window_title(const char *title);
I think I had this problem when I used Visual Studio a long time ago. I think I set a compiler setting that gave it the name of of the LIBNAME_API, but I can't remember it. How can I fix this in gcc or clang on Linux/Unix?
You need to show more code. Exactly what you have. Can you reproduce warning on gcc.godbolt.org with small code snippet? For example: https://godbolt.org/g/j4vqoe
Edited by Mārtiņš Možeiko
on
I found out what is causing it, but I don't know how to fix it, other than turn the warning off.
This link describes the problem I am having.
https://stackoverflow.com/questio...shared-library-functions-in-linux
Replace EXPORT in the code below with the LIBNAME_API I was talking about above and you get the idea.
In the case of the library code, they've used the do nothing option from above, but when I replaced it with the __GNUC__ option the warning remained. Sigh...
This link describes the problem I am having.
https://stackoverflow.com/questio...shared-library-functions-in-linux
Replace EXPORT in the code below with the LIBNAME_API I was talking about above and you get the idea.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 | #if defined(_MSC_VER)
// Microsoft
#define EXPORT __declspec(dllexport)
#define IMPORT __declspec(dllimport)
#elif defined(__GNUC__)
// GCC
#define EXPORT __attribute__((visibility("default")))
#define IMPORT
#else
// do nothing and hope for the best?
#define EXPORT
#define IMPORT
#pragma warning Unknown dynamic link import/export semantics.
#endif
|
In the case of the library code, they've used the do nothing option from above, but when I replaced it with the __GNUC__ option the warning remained. Sigh...
Edited by Mór
on