diff --git a/src/floppy/fdd_imd.c b/src/floppy/fdd_imd.c
index 814b48d..8daf57c 100644
--- a/src/floppy/fdd_imd.c
+++ b/src/floppy/fdd_imd.c
@@ -710,7 +710,7 @@ void imd_set_sector(int drive, int side, uint8_t c, uint8_t h, uint8_t r, uint8_
 	int sc = 0;
 	int sh = 0;
 	int sn = 0;
-	char *c_map, *h_map, *r_map, *n_map;
+	char *c_map = 0, *h_map = 0, *r_map = 0, *n_map = 0;
 	uint8_t id[4] = { 0, 0, 0, 0 };
 	sc = imd[drive].tracks[track][side].params[1];
 	sh = imd[drive].tracks[track][side].params[2];
@@ -753,7 +753,7 @@ void imd_writeback(int drive)
 
 	int i = 0;
 
-	char *n_map;
+	char *n_map = 0;
 
 	uint8_t h, n, spt;
 	uint32_t ssize;