Index: share/mk/bsd.compiler.mk
===================================================================
--- share/mk/bsd.compiler.mk
+++ share/mk/bsd.compiler.mk
@@ -239,15 +239,9 @@
 ${X_}COMPILER_FEATURES+=	retpoline init-all
 # PR257638 lld fails with BE compressed debug.  Fixed in main but external tool
 # chains will initially not have the fix.  For now limit the feature to LE
-# targets.
-# When compiling bootstrap tools on non-FreeBSD, the various MACHINE variables
-# for the host can be missing or not match FreeBSD's naming (e.g. Linux/amd64
-# reports as MACHINE=x86_64 MACHINE_ARCH=x86_64), causing TARGET_ENDIANNESS to
-# be undefined; be conservative and default to off until we turn this on by
-# default everywhere.
+# targets. We disable this entirely when building on non FreeBSD hosts.
 .include <bsd.endian.mk>
-.if (${.MAKE.OS} == "FreeBSD" || defined(TARGET_ENDIANNESS)) && \
-    ${TARGET_ENDIANNESS} == "1234"
+.if ${.MAKE.OS} == "FreeBSD" && ${TARGET_ENDIANNESS} == "1234"
 ${X_}COMPILER_FEATURES+=	compressed-debug
 .endif
 .endif