--- a/upb/port/def.inc
+++ b/upb/port/def.inc
@@ -239,7 +239,7 @@
 // Android uses a custom libc that does not implement all of posix, but it has
 // had sigsetjmp/siglongjmp forever on arm and since API 12 on x86. Apple has
 // sigsetjmp, but does not define the posix feature test macro.
-#if defined(__APPLE__) || defined(_POSIX_C_SOURCE) || defined(__ANDROID__)
+#if (defined(__APPLE__) || defined(_POSIX_C_SOURCE) || defined(__ANDROID__)) && !defined(__FreeBSD__)
 // avoid setting/restoring signal mask, which involves costly syscalls
 #define UPB_SETJMP(buf) sigsetjmp(buf, 0)
 #define UPB_LONGJMP(buf, val) siglongjmp(buf, val)