Bug 1718171 - Add the clang runtime directory to LIB during configure....

Bug 1718171 - Add the clang runtime directory to LIB during configure. r=firefox-build-system-reviewers,andi

We currently do so from mozconfigs, but that means this doesn't happen
for local builds.

Differential Revision: https://phabricator.services.mozilla.com/D174064

browser/config/mozconfigs/win64/code-coverage

@@ -19,7 +19,6 @@ export MOZ_PACKAGE_JSSHELL=1
 if [ -d "$MOZ_FETCHES_DIR/clang" ]; then
     CLANG_LIB_DIR="$(cd $MOZ_FETCHES_DIR/clang/lib/clang/* && cd lib/windows && pwd)"
 
-    export LIB=$LIB:$CLANG_LIB_DIR
     export LDFLAGS="clang_rt.profile-x86_64.lib"
 fi
 

build/moz.configure/windows.configure

@@ -339,9 +339,10 @@ def lib_path_for(host_or_target):
         vc_path,
         valid_windows_sdk_dir,
         valid_ucrt_sdk_dir,
+        c_compiler,
     )
     @imports("os")
-    def lib_path(target, is_host, vc_path, windows_sdk_dir, ucrt_sdk_dir):
+    def lib_path(target, is_host, vc_path, windows_sdk_dir, ucrt_sdk_dir, compiler):
         if not vc_path:
             return
         sdk_target = {
@@ -371,6 +372,15 @@ def lib_path_for(host_or_target):
                 os.path.join(ucrt_sdk_dir.lib, "ucrt", sdk_target),
             )
         )
+        if compiler.type == "clang-cl":
+            runtime_dir = check_cmd_output(
+                compiler.compiler,
+                "/clang:--print-runtime-dir",
+                *compiler.flags,
+                onerror=lambda: None
+            ).strip()
+            if runtime_dir and os.path.exists(runtime_dir):
+                libs.append(runtime_dir)
         return libs
 
     return lib_path

build/mozconfig.clang-cl

 if test -d "$MOZ_FETCHES_DIR/clang/bin"; then
     CLANG_DIR=`cd "$MOZ_FETCHES_DIR/clang/bin" ; pwd`
     export PATH="${CLANG_DIR}:${PATH}"
-
-    if $(cd $MOZ_FETCHES_DIR/clang/lib/clang/* && test -d lib/windows); then
-        export LIB="$(cd $MOZ_FETCHES_DIR/clang/lib/clang/* && cd lib/windows && pwd)"
-    fi
 fi
 
 export CC=clang-cl

build/win64/mozconfig.asan

@@ -3,7 +3,6 @@
 if [ -d "$MOZ_FETCHES_DIR/clang" ]; then
     CLANG_LIB_DIR="$(cd $MOZ_FETCHES_DIR/clang/lib/clang/* && cd lib/windows && pwd)"
 
-    export LIB=$CLANG_LIB_DIR
     export LDFLAGS="clang_rt.asan_dynamic-x86_64.lib clang_rt.asan_dynamic_runtime_thunk-x86_64.lib"
 
     export MOZ_COPY_PDBS=1

tools/sanitizer/docs/asan.rst

@@ -100,7 +100,6 @@ Run ``mach bootstrap`` to get an updated clang-cl in your
    export LDFLAGS="clang_rt.asan_dynamic-x86_64.lib clang_rt.asan_dynamic_runtime_thunk-x86_64.lib"
    CLANG_LIB_DIR="$(cd ~/.mozbuild/clang/lib/clang/*/lib/windows && pwd)"
    export MOZ_CLANG_RT_ASAN_LIB_PATH="${CLANG_LIB_DIR}/clang_rt.asan_dynamic-x86_64.dll"
-   export LIB=$LIB:$CLANG_LIB_DIR
 
 If you launch an ASan build under WinDbg, you may see spurious
 first-chance Access Violation exceptions. These come from ASan creating