[PATCH v2 1/2] rust-common: Fix use of target definitions for SDK generation

[Otavio Salvador <otavio@ossystems.com.br>]

We need full target passed for build so we changed the
rust-cross-canadian to use same code used in regular rust recipes and
added support to use specific llvm-target for the building host.

Fixes: ef566af964 ("rust: fix issue building cross-canadian tools for aarch64 on x86_64")
Fixes: bd36593ba3 ("rust-common: Drop LLVM_TARGET and simplify")
Fixes: 8ed000debb ("rust-common: Fix for target definitions returning 'NoneType' for arm")
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
---

Changes in v2:
- Fix syntax for newer Python

 meta/recipes-devtools/rust/rust-common.inc    | 21 ++++++++++++------
 .../rust/rust-cross-canadian-common.inc       | 22 ++++++++++++++++---
 2 files changed, 33 insertions(+), 10 deletions(-)

diff --git a/meta/recipes-devtools/rust/rust-common.inc b/meta/recipes-devtools/rust/rust-common.inc
index ef70c48d0f..a937d58a37 100644
--- a/meta/recipes-devtools/rust/rust-common.inc
+++ b/meta/recipes-devtools/rust/rust-common.inc
@@ -119,12 +119,12 @@ def llvm_features(d):
 
 
 ## arm-unknown-linux-gnueabihf
-DATA_LAYOUT[arm] = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
-TARGET_ENDIAN[arm] = "little"
-TARGET_POINTER_WIDTH[arm] = "32"
-TARGET_C_INT_WIDTH[arm] = "32"
-MAX_ATOMIC_WIDTH[arm] = "64"
-FEATURES[arm] = "+v6,+vfp2"
+DATA_LAYOUT[arm-eabi] = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
+TARGET_ENDIAN[arm-eabi] = "little"
+TARGET_POINTER_WIDTH[arm-eabi] = "32"
+TARGET_C_INT_WIDTH[arm-eabi] = "32"
+MAX_ATOMIC_WIDTH[arm-eabi] = "64"
+FEATURES[arm-eabi] = "+v6,+vfp2"
 
 ## armv7-unknown-linux-gnueabihf
 DATA_LAYOUT[armv7-eabi] = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
@@ -304,12 +304,19 @@ def rust_gen_target(d, thing, wd, features, cpu, arch, abi=""):
     else:
         arch_abi = rust_arch
 
+    # When building for the building system we need to return the HOST target
+    # or wrong flags are used.
+    if thing == "BUILD":
+        llvm_target = d.getVar('RUST_HOST_SYS', arch_abi)
+    else:
+        llvm_target = d.getVar('RUST_TARGET_SYS', arch_abi)
+
     features = features or d.getVarFlag('FEATURES', arch_abi) or ""
     features = features.strip()
 
     # build tspec
     tspec = {}
-    tspec['llvm-target'] = d.getVar('RUST_TARGET_SYS', arch_abi)
+    tspec['llvm-target'] = llvm_target
     tspec['data-layout'] = d.getVarFlag('DATA_LAYOUT', arch_abi)
     tspec['max-atomic-width'] = int(d.getVarFlag('MAX_ATOMIC_WIDTH', arch_abi))
     tspec['target-pointer-width'] = d.getVarFlag('TARGET_POINTER_WIDTH', arch_abi)
diff --git a/meta/recipes-devtools/rust/rust-cross-canadian-common.inc b/meta/recipes-devtools/rust/rust-cross-canadian-common.inc
index 1f21c8af26..eff9212648 100644
--- a/meta/recipes-devtools/rust/rust-cross-canadian-common.inc
+++ b/meta/recipes-devtools/rust/rust-cross-canadian-common.inc
@@ -27,9 +27,23 @@ DEBUG_PREFIX_MAP = "-fdebug-prefix-map=${WORKDIR}=/usr/src/debug/${PN}/${EXTENDP
 
 python do_rust_gen_targets () {
     wd = d.getVar('WORKDIR') + '/targets/'
-    rust_gen_target(d, 'TARGET', wd, d.getVar('TARGET_LLVM_FEATURES') or "", d.getVar('TARGET_LLVM_CPU'), d.getVar('TARGET_ARCH'))
-    rust_gen_target(d, 'HOST', wd, "", "generic", d.getVar('HOST_ARCH'))
-    rust_gen_target(d, 'BUILD', wd, "", "generic", d.getVar('BUILD_ARCH'))
+    # It is important 'TARGET' is last here so that it overrides our less
+    # informed choices for BUILD & HOST if TARGET happens to be the same as
+    # either of them.
+    for thing in ['BUILD', 'HOST', 'TARGET']:
+        bb.debug(1, "rust_gen_target for " + thing)
+        features = ""
+        cpu = "generic"
+        arch = d.getVar('{}_ARCH'.format(thing))
+        abi = ""
+        if thing is "TARGET":
+            abi = d.getVar('ABIEXTENSION')
+            # arm and armv7 have different targets in llvm
+            if arch == "arm" and target_is_armv7(d):
+                arch = 'armv7'
+            features = d.getVar('TARGET_LLVM_FEATURES') or ""
+            cpu = d.getVar('TARGET_LLVM_CPU')
+        rust_gen_target(d, thing, wd, features, cpu, arch, abi)
 }
 
 INHIBIT_DEFAULT_RUST_DEPS = "1"
@@ -45,6 +59,8 @@ python do_configure:prepend() {
     hosts = ["{}-unknown-linux-gnu".format(d.getVar("HOST_ARCH", True))]
 }
 
+INSANE_SKIP:${PN} = "libdir"
+
 INSANE_SKIP:${RUSTLIB_TARGET_PN} = "file-rdeps arch ldflags"
 SKIP_FILEDEPS:${RUSTLIB_TARGET_PN} = "1"
 
-- 
2.36.1