diff --git a/grep.c b/grep.c
index 2f8b9553df..e5761426e4 100644
--- a/grep.c
+++ b/grep.c
@@ -245,7 +245,7 @@ static int is_fixed(const char *s, size_t len)
 #ifdef USE_LIBPCRE2
 #define GREP_PCRE2_DEBUG_MALLOC 0
 
-static void *pcre2_malloc(PCRE2_SIZE size, MAYBE_UNUSED void *memory_data)
+static void *pcre2_malloc(PCRE2_SIZE size, void *memory_data UNUSED)
 {
 	void *pointer = malloc(size);
 #if GREP_PCRE2_DEBUG_MALLOC
@@ -255,7 +255,7 @@ static void *pcre2_malloc(PCRE2_SIZE size, MAYBE_UNUSED void *memory_data)
 	return pointer;
 }
 
-static void pcre2_free(void *pointer, MAYBE_UNUSED void *memory_data)
+static void pcre2_free(void *pointer, void *memory_data UNUSED)
 {
 #if GREP_PCRE2_DEBUG_MALLOC
 	static int count = 1;