Auto merge of #23256 - jdm:clang-cl, r=asajeffrey

Use clang-cl for Windows builds

Depends on https://github.com/servo/mozjs/pull/178.

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.cargo/config

@@ -22,5 +22,5 @@ ar = "arm-linux-gnueabihf-ar"
 linker = "aarch64-linux-gnu-gcc"
 ar = "aarch64-linux-gnu-ar"
 
-[target.'cfg(target_os=windows)']
-linker = "./support/android/fakeld/fake-ld.cmd"
+[target.x86_64-pc-windows-msvc]
+linker = "lld-link.exe"

Cargo.lock

@@ -2810,13 +2810,13 @@ dependencies = [
  "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "mozjs_sys 0.61.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "mozjs_sys 0.61.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "mozjs_sys"
-version = "0.61.11"
+version = "0.61.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bindgen 0.49.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -5593,7 +5593,7 @@ dependencies = [
 "checksum mitochondria 1.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9de3eca27871df31c33b807f834b94ef7d000956f57aa25c5aed9c5f0aae8f6f"
 "checksum mozangle 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "45a8a18a41cfab0fde25cc2f43ea89064d211a0fbb33225b8ff93ab20406e0e7"
 "checksum mozjs 0.10.1 (registry+https://github.com/rust-lang/crates.io-index)" = "622108d35f4fdd68b3aa39bfe9bedaee5fa9efd19711d046e1d56ff607c0a36f"
-"checksum mozjs_sys 0.61.11 (registry+https://github.com/rust-lang/crates.io-index)" = "22ab5d3738fc69d394b30e1256d2cbf5b4f1e668a7deba94f9f3726dcfc89689"
+"checksum mozjs_sys 0.61.12 (registry+https://github.com/rust-lang/crates.io-index)" = "370887111c83436555cde840bb2639c5a088c77f01b152957d99e1f279397f48"
 "checksum msdos_time 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "aad9dfe950c057b1bfe9c1f2aa51583a8468ef2a5baba2ebbe06d775efeb7729"
 "checksum muldiv 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "451a9a05d2a32c566c897835e0ea95cf79ed2fdfe957924045a1721a36c9980f"
 "checksum net2 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)" = "42550d9fb7b6684a6d404d9fa7250c2eb2646df731d1c06afc06dcee9e1bcf88"

appveyor.yml

@@ -30,6 +30,9 @@ environment:
     C:\\Program Files\\Git\\cmd;\
     C:\\Program Files\\Git\\usr\\bin;\
     C:\\Program Files\\AppVeyor\\BuildAgent;"
+  CC: "clang-cl.exe"
+  CXX: "clang-cl.exe"
+
   matrix:
   - TARGET: nightly-x86_64-pc-windows-msvc
 

components/script/build.rs

@@ -25,11 +25,6 @@ fn main() {
         // We must use Ninja on Windows for this -- msbuild is painfully slow,
         // and ninja is easier to install than make.
         build.generator("Ninja");
-        // because we're using ninja, we need to explicitly set these
-        // to VC++, otherwise it'll try to use cc
-        build
-            .define("CMAKE_C_COMPILER", "cl.exe")
-            .define("CMAKE_CXX_COMPILER", "cl.exe");
         // We have to explicitly specify the full path to link.exe,
         // for reasons that I don't understand.  If we just give
         // link.exe, it tries to use script-*/out/link.exe, which of

python/servo/build_commands.py

@@ -310,6 +310,10 @@ class MachCommands(CommandBase):
         if with_debug_assertions:
             env['RUSTFLAGS'] = env.get('RUSTFLAGS', "") + " -C debug_assertions"
 
+        if sys.platform == "win32":
+            env["CC"] = "clang-cl.exe"
+            env["CXX"] = "clang-cl.exe"
+
         if android:
             if "ANDROID_NDK" not in env:
                 print("Please set the ANDROID_NDK environment variable.")

python/servo/packages.py

@@ -3,7 +3,7 @@
 # You can obtain one at https://mozilla.org/MPL/2.0/.
 
 WINDOWS_MSVC = {
-    "cmake": "3.7.2",
+    "cmake": "3.14.3",
     "llvm": "7.0.0",
     "moztools": "3.2",
     "ninja": "1.7.1",