diff --git a/git-compat-util.h b/git-compat-util.h
index d0c0884fc9..d85fdf5415 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -508,6 +508,7 @@ int mingw_rename(const char*, const char*);
 static inline int fsync(int fd) { return 0; }
 static inline int getppid(void) { return 1; }
 static inline void sync(void) {}
+extern int getpagesize(void);	/* defined in MinGW's libgcc.a */
 
 extern void quote_argv(const char **dst, const char **src);
 extern const char *parse_interpreter(const char *cmd);