cross-canadian/meta-environment: Allow modification of TARGET_OS to be optional

There are some cases we want the manipulation cross-canadian performance
on TARGET_OS, there are also cases like meta-environment where we do not
want this manipulation.

We did try and use immediate expansion to avoid this problem and it
works in the non multilib case. If we have a multilib that used an
extension, like for example:

require conf/multilib.conf
MULTILIBS = "multilib:lib32 multilib:lib64"
DEFAULTTUNE = "mips32r2"
DEFAULTTUNE_virtclass-multilib-lib32 = "mips64-n32"
DEFAULTTUNE_virtclass-multilib-lib64 = "mips64"

then the n32 extension case will be misconfigured.

It turns out saving an unexpanded variable is hard. The best I could
come up with was:

SAVEDTOS := "${@d.getVar('TARGET_OS', False).replace("{", "*")}"

and then

localdata.setVar("TARGET_OS", d.getVar("SAVEDOS", False).replace('*','{'))

which is rather evil, I'd challenge someone to come up with a nicer way
of making it work though!

Rather than the above madness, we modify cross-canadian to make the
problamtic code conditional.

This fixes the original issue (where a linux-gnuspe target was seeing
'linux') of
http://cgit.openembedded.org/openembedded-core/commit/?id=0038634ee6e2b6035c023a2702547f20f67c103a
but also fixes the multilib one.

(From OE-Core rev: 85ff3d6491c54aa712ed238c561742cda4f4ba07)

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

meta/classes/cross-canadian.bbclass

@@ -16,6 +16,7 @@ STAGING_BINDIR_TOOLCHAIN = "${STAGING_DIR_NATIVE}${bindir_native}/${SDK_ARCH}${S
 #
 PACKAGE_ARCH = "${SDK_ARCH}-${SDKPKGSUFFIX}"
 CANADIANEXTRAOS = ""
+MODIFYTOS ??= "1"
 python () {
     archs = d.getVar('PACKAGE_ARCHS', True).split()
     sdkarchs = []
@@ -23,6 +24,9 @@ python () {
         sdkarchs.append(arch + '-${SDKPKGSUFFIX}')
     d.setVar('PACKAGE_ARCHS', " ".join(sdkarchs))
 
+    # Allow the following code segment to be disabled, e.g. meta-environment
+    if d.getVar("MODIFYTOS", True) != "1":
+        return
     # PowerPC can build "linux" and "linux-gnuspe"
     tarch = d.getVar("TARGET_ARCH", True)
     if tarch == "powerpc":

meta/recipes-core/meta/meta-environment.bb

@@ -6,9 +6,9 @@ PR = "r8"
 
 EXCLUDE_FROM_WORLD = "1"
 
-ORIGOS := "${TARGET_OS}"
+MODIFYTOS = "0"
 
-REAL_MULTIMACH_TARGET_SYS = "${TUNE_PKGARCH}${TARGET_VENDOR}-${ORIGOS}"
+REAL_MULTIMACH_TARGET_SYS = "${TUNE_PKGARCH}${TARGET_VENDOR}-${TARGET_OS}"
 
 inherit toolchain-scripts
 TOOLCHAIN_NEED_CONFIGSITE_CACHE += "zlib"
@@ -30,7 +30,6 @@ python do_generate_content() {
 
     # make sure we only use the SDKTARGETSYSROOT value from 'd'
     localdata.setVar('SDKTARGETSYSROOT', d.getVar('SDKTARGETSYSROOT', True))
-    localdata.setVar('TARGET_OS', d.getVar('ORIGOS', True))
     localdata.setVar('libdir', d.getVar('target_libdir', False))
 
     # Process DEFAULTTUNE