--- a/upb/wire/encode.c
+++ b/upb/wire/encode.c
@@ -187,7 +187,7 @@
       "br %[addr]\n"
       // Work around llvm/llvm-project#47432, where alignment directives inside
       // functions crash the compiler when generating SEH info on windows.
-      #ifndef __SEH__
+      #if !defined(__SEH__) && !defined(_WIN32)
       ".p2align " UPB_BTI_SHIFT_IMM
       #endif
       "0:\n"