diff --git a/libpkgconf/parser.c b/libpkgconf/parser.c
index 17aa697..7ac9362 100644
--- a/libpkgconf/parser.c
+++ b/libpkgconf/parser.c
@@ -66,8 +66,11 @@ pkgconf_parser_parse(FILE *f, void *data, const pkgconf_parser_operand_func_t *o
 		}
 
 		op = *p;
-		*p = '\0';
-		p++;
+		if (*p != '\0')
+		{
+			*p = '\0';
+			p++;
+		}
 
 		while (*p && isspace((unsigned int)*p))
 			p++;