ProjectExplorer: Search for clang-cl compiler in path

Currently we only check if it's in the registry which
is not the case when you have a custom build.

Change-Id: I20ec25378d16996f790726ed14238861bc220004
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>

1 files changed, 34 insertions, 17 deletions

diff --git a/src/plugins/projectexplorer/msvctoolchain.cpp b/src/plugins/projectexplorer/msvctoolchain.cpp
index aead49aa6ce..24491e15982 100644
--- a/src/plugins/projectexplorer/msvctoolchain.cpp
+++ b/src/plugins/projectexplorer/msvctoolchain.cpp
@@ -1008,26 +1008,18 @@ static const ToolChain *selectMsvcToolChain(const QString &clangClPath,
     return toolChain;
 }
 
-// Detect Clang-cl on top of MSVC2017, MSVC2015 or MSVC2013.
-static void detectClangClToolChain(QList<ToolChain *> *list)
+static void detectClangClToolChainInPath(const QString &clangClPath, QList<ToolChain *> *list)
 {
-#ifdef Q_OS_WIN64
-    const char registryNode[] = "HKEY_LOCAL_MACHINE\\SOFTWARE\\WOW6432Node\\LLVM\\LLVM";
-#else
-    const char registryNode[] = "HKEY_LOCAL_MACHINE\\SOFTWARE\\LLVM\\LLVM";
-#endif
-
-    const QSettings registry(QLatin1String(registryNode), QSettings::NativeFormat);
-    if (registry.status() != QSettings::NoError)
-        return;
-    const QString path = QDir::cleanPath(registry.value(QStringLiteral(".")).toString());
-    if (path.isEmpty())
-        return;
-    const QString clangClPath = compilerFromPath(path);
     const unsigned char wordWidth = Utils::is64BitWindowsBinary(clangClPath) ? 64 : 32;
     const ToolChain *toolChain = selectMsvcToolChain(clangClPath, *list, wordWidth);
+
+    QDir path = QFileInfo(clangClPath).absoluteDir(); // bin folder
+    path.cdUp(); // cd to LLVM root
+    const QString rootPath = path.canonicalPath();
+
     if (!toolChain) {
-        qWarning("Unable to find a suitable MSVC version for \"%s\".", qPrintable(QDir::toNativeSeparators(path)));
+        qWarning("Unable to find a suitable MSVC version for \"%s\".",
+                 qPrintable(QDir::toNativeSeparators(rootPath)));
         return;
     }
     const MsvcToolChain *msvcToolChain = static_cast<const MsvcToolChain *>(toolChain);
@@ -1036,12 +1028,37 @@ static void detectClangClToolChain(QList<ToolChain *> *list)
         + QStringLiteral("bit based on ")
         + Abi::toString(targetAbi.osFlavor()).toUpper();
     for (auto language: {Constants::C_LANGUAGE_ID, Constants::CXX_LANGUAGE_ID}) {
-        list->append(new ClangClToolChain(name, path, targetAbi,
+        list->append(new ClangClToolChain(name, rootPath, targetAbi,
                                           msvcToolChain->varsBat(), msvcToolChain->varsBatArg(),
                                           language, ToolChain::AutoDetection));
     }
 }
 
+// Detect Clang-cl on top of MSVC2017, MSVC2015 or MSVC2013.
+static void detectClangClToolChain(QList<ToolChain *> *list)
+{
+#ifdef Q_OS_WIN64
+    const char registryNode[] = "HKEY_LOCAL_MACHINE\\SOFTWARE\\WOW6432Node\\LLVM\\LLVM";
+#else
+    const char registryNode[] = "HKEY_LOCAL_MACHINE\\SOFTWARE\\LLVM\\LLVM";
+#endif
+
+    const QSettings registry(QLatin1String(registryNode), QSettings::NativeFormat);
+    if (registry.status() == QSettings::NoError) {
+        const QString path = QDir::cleanPath(registry.value(QStringLiteral(".")).toString());
+        const QString clangClPath = compilerFromPath(path);
+        if (!path.isEmpty()) {
+            detectClangClToolChainInPath(path, list);
+            return;
+        }
+    }
+
+    const Utils::Environment systemEnvironment = Utils::Environment::systemEnvironment();
+    const Utils::FileName clangClPath = systemEnvironment.searchInPath("clang-cl");
+    if (!clangClPath.isEmpty())
+        detectClangClToolChainInPath(clangClPath.toString(), list);
+}
+
 QList<ToolChain *> MsvcToolChainFactory::autoDetect(const QList<ToolChain *> &alreadyKnown)
 {
     QList<ToolChain *> results;