Don't crash on an invalid guessdir

diff --git a/src/uncommon.c b/src/uncommon.c
index 946924e856ff1b97f09101d6bb0f70d38f9706aa..692191a36aa2c34aced7c764443ebccff518fe1a 100644 (file)
--- a/src/uncommon.c
+++ b/src/uncommon.c
@@ -54,7 +54,7 @@ int ick_printfopens=0;
   /*@observer@*/ static const char *fileiter;
   size_t i = 0, j;
   FILE* ret;
-  while(*guessdir != '\0' && i<BUFSIZ-2) buf2[i++] = *guessdir++;
+  while(guessdir && *guessdir != '\0' && i<BUFSIZ-2) buf2[i++] = *guessdir++;
   buf2[i++] = '/';
   fileiter = file;
   while(*fileiter != '\0' && i<BUFSIZ-1) buf2[i++] = *fileiter++;
@@ -107,7 +107,7 @@ int ick_printfopens=0;
   /*@observer@*/ static const char *fileiter;
   size_t i = 0, j;
   FILE* ret;
-  while(*guessdir != '\0' && i<BUFSIZ-2) buf2[i++] = *guessdir++;
+  while(guessdir && *guessdir != '\0' && i<BUFSIZ-2) buf2[i++] = *guessdir++;
   buf2[i++] = '/';
   fileiter = file;
   while(*fileiter != '\0' && i<BUFSIZ-1) buf2[i++] = *fileiter++;