diff --git a/meta/recipes-devtools/flex/flex/0001-Match-malloc-signature-to-its-use.patch b/meta/recipes-devtools/flex/flex/0001-Match-malloc-signature-to-its-use.patch
new file mode 100644
index 0000000000..fc3b8c563d
--- /dev/null
+++ b/meta/recipes-devtools/flex/flex/0001-Match-malloc-signature-to-its-use.patch
@@ -0,0 +1,25 @@
+From cec508013706ef06dbac036905a90cbe075fa03d Mon Sep 17 00:00:00 2001
+From: Richard Barnes <rbarnes@umn.edu>
+Date: Wed, 2 Oct 2024 10:35:09 -0700
+Subject: [PATCH] Match `malloc` signature to its use
+
+Upstream-Status: Submitted [https://github.com/westes/flex/pull/674]
+
+Signed-off-by: Martin Jansa <martin.jansa@gmail.com>
+---
+ lib/malloc.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/lib/malloc.c b/lib/malloc.c
+index 75e8ef9..701b9b3 100755
+--- a/lib/malloc.c
++++ b/lib/malloc.c
+@@ -3,7 +3,7 @@
+      
+      #include <sys/types.h>
+      
+-     void *malloc ();
++     void *malloc (size_t n);
+      
+      /* Allocate an N-byte block of memory from the heap.
+         If N is zero, allocate a 1-byte block.  */
diff --git a/meta/recipes-devtools/flex/flex_2.6.4.bb b/meta/recipes-devtools/flex/flex_2.6.4.bb
index f7d4ef1f08..52543b6e02 100644
--- a/meta/recipes-devtools/flex/flex_2.6.4.bb
+++ b/meta/recipes-devtools/flex/flex_2.6.4.bb
@@ -19,6 +19,7 @@ SRC_URI = "${GITHUB_BASE_URI}/download/v${PV}/flex-${PV}.tar.gz \
            file://0001-build-AC_USE_SYSTEM_EXTENSIONS-in-configure.ac.patch \
            file://check-funcs.patch \
            file://0001-Emit-no-line-directives-if-gen_line_dirs-is-false.patch \
+           file://0001-Match-malloc-signature-to-its-use.patch \
            "
 
 SRC_URI[md5sum] = "2882e3179748cc9f9c23ec593d6adc8d"