diff --git a/pkgs/tools/text/diffutils/default.nix b/pkgs/tools/text/diffutils/default.nix
index 916dc2255576..d82686d98c3e 100644
--- a/pkgs/tools/text/diffutils/default.nix
+++ b/pkgs/tools/text/diffutils/default.nix
@@ -31,6 +31,9 @@ stdenv.mkDerivation rec {
     # https://lists.gnu.org/archive/html/bug-gnulib/2025-07/msg00021.html
     # Multiple upstream commits squashed with adjustments, see header
     ./gnulib-float-h-tests-port-to-C23-PowerPC-GCC.patch
+  ]
+  ++ lib.optionals stdenv.hostPlatform.useLLVM [
+    ./musl-llvm.patch
   ];
 
   nativeBuildInputs = [
diff --git a/pkgs/tools/text/diffutils/musl-llvm.patch b/pkgs/tools/text/diffutils/musl-llvm.patch
new file mode 100644
index 000000000000..535a64d1ab79
--- /dev/null
+++ b/pkgs/tools/text/diffutils/musl-llvm.patch
@@ -0,0 +1,15 @@
+---
+ gnulib-tests/test-c32ispunct.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/gnulib-tests/test-c32ispunct.c
++++ b/gnulib-tests/test-c32ispunct.c
+@@ -255,7 +255,7 @@ main (int argc, char *argv[])
+           is = for_character ("\360\235\204\200", 4);
+           ASSERT (is != 0);
+         #endif
+-        #if !(defined __GLIBC__ || (defined __APPLE__ && defined __MACH__) || defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__ || defined _AIX || defined __sun || defined __CYGWIN__ || (defined _WIN32 && !defined __CYGWIN__) || defined __ANDROID__)
++        #if !(defined __GLIBC__ || defined MUSL_LIBC || (defined __APPLE__ && defined __MACH__) || defined __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__ || defined _AIX || defined __sun || defined __CYGWIN__ || (defined _WIN32 && !defined __CYGWIN__) || defined __ANDROID__)
+           /* U+E003A TAG COLON */
+           is = for_character ("\363\240\200\272", 4);
+           ASSERT (is == 0);