diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c
index fd1728d94bab..59fe69a63800 100644
--- a/lib/lz4/lz4_decompress.c
+++ b/lib/lz4/lz4_decompress.c
@@ -507,9 +507,9 @@ static int LZ4_decompress_safe_withSmallPrefix(const char *source, char *dest,
 				      (BYTE *)dest - prefixSize, NULL, 0);
 }
 
-int LZ4_decompress_safe_forceExtDict(const char *source, char *dest,
-				     int compressedSize, int maxOutputSize,
-				     const void *dictStart, size_t dictSize)
+static int LZ4_decompress_safe_forceExtDict(const char *source, char *dest,
+					    int compressedSize, int maxOutputSize,
+					    const void *dictStart, size_t dictSize)
 {
 	return LZ4_decompress_generic(source, dest,
 				      compressedSize, maxOutputSize,