diff -Nur cdogs-sdl-0.9.0/src/cdogs/log.c new/src/cdogs/log.c
--- cdogs-sdl-0.9.0/src/cdogs/log.c	2020-09-16 15:27:30.000000000 +0200
+++ new/src/cdogs/log.c	2020-09-30 13:06:55.179642290 +0200
@@ -32,6 +32,7 @@
 #include "rlutil/rlutil.h"
 #include "utils.h"
 
+FILE *gLogFile;
 
 typedef struct
 {
diff -Nur cdogs-sdl-0.9.0/src/cdogs/log.h new/src/cdogs/log.h
--- cdogs-sdl-0.9.0/src/cdogs/log.h	2020-09-16 15:27:30.000000000 +0200
+++ new/src/cdogs/log.h	2020-09-30 13:06:34.435491593 +0200
@@ -60,7 +60,7 @@
 const char *LogLevelName(const LogLevel l);
 LogLevel StrLogLevel(const char *s);
 
-FILE *gLogFile;
+extern FILE *gLogFile;
 void LogInit(void);
 void LogOpenFile(const char *filename);
 void LogTerminate(void);