[runtime] Add a configure workaround for apple silicon + older config… (#40184)

….guess versions.

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Co-authored-by: vargaz <[email protected]>

Author: monojenkins

src/mono/configure.ac

@@ -408,6 +408,13 @@ case "$host" in
 		host_sunos=yes
 		;;
 	*-*-darwin*)
+		# Temporary workaround for Apple Silicon
+		# config.guess returns arm-apple-darwin20.0.0
+		if test $ac_cv_host = arm-apple-darwin20.0.0 -o $ac_cv_target = arm-apple-darwin20.0.0; then
+		   echo "You are running on Apple Silicon, but using an old config.guess, invoke configure like this:"
+		   echo "Run configure using ./configure --host=aarch64-apple-darwin20.0.0 --target=aarch64-apple-darwin20.0.0"
+		   exit 1
+		fi
 		parallel_mark="Disabled_Currently_Hangs_On_MacOSX"
 		host_darwin=yes
 		target_mach=yes