From 6a3e138431f4330cea0dd23c3a6f81da422a587e Mon Sep 17 00:00:00 2001
From: Marc-Andre Laperle <malaperle@gmail.com>
Date: Tue, 15 Sep 2020 23:45:43 -0400
Subject: [PATCH] Bug 567018 - Built-in language settings provider for Clang-cl

It is the same as GCC built-in provider but with tweaked parameters to
pass to Clang driver. It has to be enabled by hand since there is no
toolchain associated with it for now.

Change-Id: I5455d04725b2ee4709844d32ee32d355d120d807
Signed-off-by: Marc-Andre Laperle <malaperle@gmail.com>
---
 .../plugin.properties                         |  1 +
 windows/org.eclipse.cdt.msw.build/plugin.xml  | 12 ++++++++
 .../core/ClangClBuiltinSpecsDetector.java     | 30 +++++++++++++++++++
 3 files changed, 43 insertions(+)
 create mode 100644 windows/org.eclipse.cdt.msw.build/src/org/eclipse/cdt/internal/msw/build/core/ClangClBuiltinSpecsDetector.java

diff --git a/windows/org.eclipse.cdt.msw.build/plugin.properties b/windows/org.eclipse.cdt.msw.build/plugin.properties
index 272a006cae7..f4bbed266a6 100644
--- a/windows/org.eclipse.cdt.msw.build/plugin.properties
+++ b/windows/org.eclipse.cdt.msw.build/plugin.properties
@@ -14,3 +14,4 @@ config.debug=Debug
 config.release=Release
 
 MSVCOutputParser.name = MSVC Build Output Parser
+ClangCLBuiltinSpecsDetector.name = Clang-cl Built-in Compiler Settings
\ No newline at end of file
diff --git a/windows/org.eclipse.cdt.msw.build/plugin.xml b/windows/org.eclipse.cdt.msw.build/plugin.xml
index 1476eaa756e..c8e8d75b575 100644
--- a/windows/org.eclipse.cdt.msw.build/plugin.xml
+++ b/windows/org.eclipse.cdt.msw.build/plugin.xml
@@ -762,4 +762,16 @@
             prefer-non-shared="true">
       </provider>
    </extension>
+   <extension
+         point="org.eclipse.cdt.core.LanguageSettingsProvider">
+      <provider
+            class="org.eclipse.cdt.internal.msw.build.core.ClangClBuiltinSpecsDetector"
+            id="org.eclipse.cdt.msw.build.core.ClangCLBuiltinSpecsDetector"
+            name="%ClangCLBuiltinSpecsDetector.name"
+            parameter="${COMMAND} ${FLAGS} -E /clang:-P -v /clang:-dD &quot;${INPUTS}&quot;"
+            prefer-non-shared="true">
+         <language-scope id="org.eclipse.cdt.core.gcc"/>
+         <language-scope id="org.eclipse.cdt.core.g++"/>
+      </provider>
+   </extension>
 </plugin>
diff --git a/windows/org.eclipse.cdt.msw.build/src/org/eclipse/cdt/internal/msw/build/core/ClangClBuiltinSpecsDetector.java b/windows/org.eclipse.cdt.msw.build/src/org/eclipse/cdt/internal/msw/build/core/ClangClBuiltinSpecsDetector.java
new file mode 100644
index 00000000000..da228061f6f
--- /dev/null
+++ b/windows/org.eclipse.cdt.msw.build/src/org/eclipse/cdt/internal/msw/build/core/ClangClBuiltinSpecsDetector.java
@@ -0,0 +1,30 @@
+/*******************************************************************************
+ * Copyright (c) 2020 Marc-Andre Laperle.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package org.eclipse.cdt.internal.msw.build.core;
+
+import org.eclipse.cdt.managedbuilder.language.settings.providers.GCCBuiltinSpecsDetector;
+
+/**
+ * Language settings provider to detect built-in compiler settings for the Clang-cl compiler.
+ */
+public class ClangClBuiltinSpecsDetector extends GCCBuiltinSpecsDetector {
+
+	// This ID is mostly used for the global provider case to get the compiler command from the toolchain
+	// which will be wrong here (cl instead of clang-cl), although less wrong than GCC. We would need a dedicated
+	// Clang-cl toolchain to make the global case work.
+	// But it will correctly display whether or not the associated toolchain (MSVC) is installed and supported, instead of checking GCC.
+	private static final String TOOLCHAIN_ID = "org.eclipse.cdt.msvc.toolchain.base"; //$NON-NLS-1$
+
+	@Override
+	public String getToolchainId() {
+		return TOOLCHAIN_ID;
+	}
+}