diff --git a/src/libFLAC/format.c b/src/libFLAC/format.c
index 3513346..60b5545 100644
--- a/src/libFLAC/format.c
+++ b/src/libFLAC/format.c
@@ -44,6 +44,13 @@
 #endif
 #define min(a,b) ((a)<(b)?(a):(b))
 
+/* adjust for compilers that can't understand using LLU suffix for uint64_t literals */
+#ifdef _MSC_VER
+#define FLAC__U64L(x) x
+#else
+#define FLAC__U64L(x) x##LLU
+#endif
+
 /* VERSION should come from configure */
 FLAC_API const char *FLAC__VERSION_STRING = VERSION;
 
@@ -74,7 +81,7 @@
 FLAC_API const unsigned FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN = 64; /* bits */
 FLAC_API const unsigned FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN = 16; /* bits */
 
-FLAC_API const FLAC__uint64 FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER = 0xffffffffffffffff;
+FLAC_API const FLAC__uint64 FLAC__STREAM_METADATA_SEEKPOINT_PLACEHOLDER = FLAC__U64L(0xffffffffffffffff);
 
 FLAC_API const unsigned FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN = 32; /* bits */
 FLAC_API const unsigned FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN = 32; /* bits */