fix compiler warnings
diff --git a/src/flac/main.c b/src/flac/main.c
index 250ae1e..06a61c2 100644
--- a/src/flac/main.c
+++ b/src/flac/main.c
@@ -1800,7 +1800,7 @@
 	if(encode_infile != stdin && grabbag__file_are_same(infilename, outfilename)) {
 		static const char *tmp_suffix = ".tmp,fl-ac+en'c";
 		/*@@@@ still a remote possibility that a file with this filename exists */
-		if(0 == (internal_outfilename = malloc(strlen(outfilename)+strlen(tmp_suffix)+1))) {
+		if(0 == (internal_outfilename = (char *)malloc(strlen(outfilename)+strlen(tmp_suffix)+1))) {
 			flac__utils_printf(stderr, 1, "ERROR allocating memory for tempfile name\n");
 			conditional_fclose(encode_infile);
 			return 1;