crossdev: change USE=vtv to whitelist

Gentoo profiles enable vtv only for x86, amd64, arm and arm64.
vtv is known to be broken at least for:
- musl libc
- bare metal targets
- powerpc, powerpc64 (compiler SEGISEGVs: bug #618786)
- hppa, ia64 (missing vtv crt* files)

User can still explicitly enable vtv by tweaking
    /etc/portage/package.use/cross-${CTARGET}

Bug: https://bugs.gentoo.org/618786
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>

1 files changed, 23 insertions, 1 deletions

diff --git a/crossdev b/crossdev
index 76f9a06..06d2775 100755
--- a/crossdev
+++ b/crossdev
@@ -335,7 +335,7 @@ parse_target() {
 	esac
 
 	local sanitizer_support=no
-	# Whitelist asan on explicitly supported arches fo linux.
+	# Whitelist asan on explicitly supported arches for linux.
 	# Broken examples:
 	# - musl libc
 	# - bare metal targets
@@ -357,6 +357,28 @@ parse_target() {
 	if [[ $sanitizer_support = "no" ]]; then
 		GUSE+=" -sanitize"
 	fi
+
+	local vtv_support=no
+	# Whitelist asan on explicitly supported arches for linux.
+	# Broken examples:
+	# - musl libc
+	# - bare metal targets
+	# - powerpc
+	# Untested examples:
+	# - *BSD
+	case ${CTARGET} in
+		# glibc targets
+		*-gnu*)
+			case ${CTARGET} in
+				x86_64*|i?86*|arm*|aarch64)
+					vtv_support=yes
+					;;
+			esac
+			;;
+	esac
+	if [[ $vtv_support = "no" ]]; then
+		GUSE+=" -vtv"
+	fi
 }
 
 parse_repo_config() {