ffmpeg upstream for some reason really wants it to be broken...

--- a/libavutil/macros.h
+++ b/libavutil/macros.h	2026-02-23 04:56:53.000000000 +0800
@@ -27,6 +27,8 @@
 
 #include "libavutil/avconfig.h"
 
+#define static_assert _Static_assert
+
 #if AV_HAVE_BIGENDIAN
 #   define AV_NE(be, le) (be)
 #else

--- a/configure
+++ b/configure	2026-02-23 04:56:53.000000000 +0800
@@ -5643,7 +5644,7 @@
     int a;
     void *ptr;
 } obj;
-static_assert(offsetof(struct Foo, a) == 0,
+_Static_assert(offsetof(struct Foo, a) == 0,
               "First element of struct does not have offset 0");
 _Static_assert(offsetof(struct Foo, ptr) >= offsetof(struct Foo, a) + sizeof(obj.a),
                "elements not properly ordered in struct");