[PATCH] toolchain-scrpts: Fix sitecache issues with multilib

[Richard Purdie <richard.purdie@linuxfoundation.org>]

The use of TCLIBC in TOOLCHAIN_NEED_CONFIGSITE_CACHE is problematic
since a multilib may have both uclibc and glibc for different multilibs
yet switching between them doesn't change TCLIBC. This would result
in "lib32-glibc" being attempted when lib32 was actually uclibc.

The fix here is to use the virtual providers which bitbake switches
to point correctly at the right things.

This does mean we need to resolve virtual providers but we can do this using
sysroot-providers.

[YCOTO #7607]

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/meta/classes/toolchain-scripts.bbclass b/meta/classes/toolchain-scripts.bbclass
index 59a122f..16db511 100644
--- a/meta/classes/toolchain-scripts.bbclass
+++ b/meta/classes/toolchain-scripts.bbclass
@@ -98,7 +98,7 @@ EOF
 #we get the cached site config in the runtime
 TOOLCHAIN_CONFIGSITE_NOCACHE = "${@siteinfo_get_files(d, True)}"
 TOOLCHAIN_CONFIGSITE_SYSROOTCACHE = "${STAGING_DIR}/${MLPREFIX}${MACHINE}/${target_datadir}/${TARGET_SYS}_config_site.d"
-TOOLCHAIN_NEED_CONFIGSITE_CACHE ??= "${TCLIBC} ncurses"
+TOOLCHAIN_NEED_CONFIGSITE_CACHE ??= "virtual/libc ncurses"
 
 #This function create a site config file
 toolchain_create_sdk_siteconfig () {
@@ -113,6 +113,12 @@ toolchain_create_sdk_siteconfig () {
 
 	#get cached site config
 	for sitefile in ${TOOLCHAIN_NEED_CONFIGSITE_CACHE}; do
+		# Resolve virtual/* names to the real recipe name using sysroot-providers info
+		case $sitefile in virtual/*)
+			sitefile=`echo $sitefile | tr / _`
+			sitefile=`cat ${STAGING_DIR_TARGET}/sysroot-providers/$sitefile`
+		esac
+
 		if [ -r ${TOOLCHAIN_CONFIGSITE_SYSROOTCACHE}/${sitefile}_config ]; then
 			cat ${TOOLCHAIN_CONFIGSITE_SYSROOTCACHE}/${sitefile}_config >> $siteconfig
 		fi