git_fopen: fix a sparse 'not declared' warning

If git is built with the FREAD_READS_DIRECTORIES build variable set, this
would cause sparse to issue a 'not declared, should it be static?' warning
on Linux. This is a result of the method employed by 'compat/fopen.c' to
suppress the (possible) redefinition of the (system) fopen macro, which
also removes the extern declaration of the git_fopen function.

In order to suppress the warning, introduce a new macro to suppress the
definition (or possibly the re-definition) of the fopen symbol as a macro
override. This new macro (SUPPRESS_FOPEN_REDEFINITION) is only defined in
'compat/fopen.c', just prior to the inclusion of the 'git-compat-util.h'
header file.

Signed-off-by: Ramsay Jones <>
Signed-off-by: Junio C Hamano <>
Ramsay Jones 5 years ago committed by Junio C Hamano
parent d2bbb7c2bc
commit b0a642ac46
  1. 4
  2. 10

@ -1,14 +1,14 @@
* The order of the following two lines is important.
* FREAD_READS_DIRECTORIES is undefined before including git-compat-util.h
* SUPPRESS_FOPEN_REDEFINITION is defined before including git-compat-util.h
* to avoid the redefinition of fopen within git-compat-util.h. This is
* necessary since fopen is a macro on some platforms which may be set
* based on compiler options. For example, on AIX fopen is set to fopen64
* when _LARGE_FILES is defined. The previous technique of merely undefining
* fopen after including git-compat-util.h is inadequate in this case.
#include "../git-compat-util.h"
FILE *git_fopen(const char *path, const char *mode)

@ -689,10 +689,12 @@ char *gitstrdup(const char *s);
#ifdef fopen
#undef fopen
#define fopen(a,b) git_fopen(a,b)
# ifdef fopen
# undef fopen
# endif
# define fopen(a,b) git_fopen(a,b)
# endif
extern FILE *git_fopen(const char*, const char*);