Make CMake support more resilient.

Add c++ to GCCToolChain since that's what CMake uses by default for
MinGW. Synchronize the scannerInfoCache loading. Double check for
toolchain files at load time for configs that don't have any.

Change-Id: I8071e285ce5deb1448cabd45f394c62fe6a7f2f4

4 files changed, 23 insertions, 10 deletions

diff --git a/build/org.eclipse.cdt.build.gcc.core/src/org/eclipse/cdt/build/gcc/core/GCCToolChain.java b/build/org.eclipse.cdt.build.gcc.core/src/org/eclipse/cdt/build/gcc/core/GCCToolChain.java
index 4665dda940e..1425a4f0da8 100644
--- a/build/org.eclipse.cdt.build.gcc.core/src/org/eclipse/cdt/build/gcc/core/GCCToolChain.java
+++ b/build/org.eclipse.cdt.build.gcc.core/src/org/eclipse/cdt/build/gcc/core/GCCToolChain.java
@@ -474,7 +474,8 @@ public class GCCToolChain extends PlatformObject implements IToolChain {
 			cppCommand = null;
 			if (cCommand.contains("gcc")) { //$NON-NLS-1$
 				cppCommand = cCommand.replace("gcc", "g++"); //$NON-NLS-1$ //$NON-NLS-2$
-				commands = new String[] { cCommand, cppCommand };
+				// Also recognize c++ as an alias for g++
+				commands = new String[] { cCommand, cppCommand, cCommand.replace("gcc", "c++") }; //$NON-NLS-1$ //$NON-NLS-2$
 			} else if (cCommand.contains("clang")) { //$NON-NLS-1$
 				cppCommand = cCommand.replace("clang", "clang++"); //$NON-NLS-1$ //$NON-NLS-2$
 				commands = new String[] { cCommand, cppCommand };
diff --git a/build/org.eclipse.cdt.cmake.core/src/org/eclipse/cdt/cmake/core/internal/CMakeBuildConfiguration.java b/build/org.eclipse.cdt.cmake.core/src/org/eclipse/cdt/cmake/core/internal/CMakeBuildConfiguration.java
index 0d9a9c06ac6..1308426d97d 100644
--- a/build/org.eclipse.cdt.cmake.core/src/org/eclipse/cdt/cmake/core/internal/CMakeBuildConfiguration.java
+++ b/build/org.eclipse.cdt.cmake.core/src/org/eclipse/cdt/cmake/core/internal/CMakeBuildConfiguration.java
@@ -58,6 +58,16 @@ public class CMakeBuildConfiguration extends CBuildConfiguration {
 		if (!pathStr.isEmpty()) {
 			Path path = Paths.get(pathStr);
 			toolChainFile = manager.getToolChainFile(path);
+		} else {
+			toolChainFile = manager.getToolChainFileFor(getToolChain());
+			if (toolChainFile != null) {
+				settings.put(TOOLCHAIN_FILE, toolChainFile.getPath().toString());
+				try {
+					settings.flush();
+				} catch (BackingStoreException e) {
+					Activator.log(e);
+				}
+			}
 		}
 	}
 
@@ -70,6 +80,10 @@ public class CMakeBuildConfiguration extends CBuildConfiguration {
 		super(config, name, toolChain, launchMode);
 		this.toolChainFile = toolChainFile;
 
+		saveToolChainFile();
+	}
+
+	private void saveToolChainFile() {
 		if (toolChainFile != null) {
 			Preferences settings = getSettings();
 			settings.put(TOOLCHAIN_FILE, toolChainFile.getPath().toString());
@@ -81,10 +95,6 @@ public class CMakeBuildConfiguration extends CBuildConfiguration {
 		}
 	}
 
-	public ICMakeToolChainFile getToolChainFile() {
-		return toolChainFile;
-	}
-
 	@Override
 	public IProject[] build(int kind, Map<String, String> args, IConsole console, IProgressMonitor monitor)
 			throws CoreException {
diff --git a/build/org.eclipse.cdt.cmake.core/src/org/eclipse/cdt/cmake/core/internal/CMakeBuildConfigurationProvider.java b/build/org.eclipse.cdt.cmake.core/src/org/eclipse/cdt/cmake/core/internal/CMakeBuildConfigurationProvider.java
index 71916f5d22a..2ffd0864ed1 100644
--- a/build/org.eclipse.cdt.cmake.core/src/org/eclipse/cdt/cmake/core/internal/CMakeBuildConfigurationProvider.java
+++ b/build/org.eclipse.cdt.cmake.core/src/org/eclipse/cdt/cmake/core/internal/CMakeBuildConfigurationProvider.java
@@ -83,10 +83,12 @@ public class CMakeBuildConfigurationProvider implements ICBuildConfigurationProv
 		if (arch != null && !arch.isEmpty()) {
 			properties.put(IToolChain.ATTR_ARCH, arch);
 		}
-		ICMakeToolChainFile file = null;
-		Collection<ICMakeToolChainFile> files = manager.getToolChainFilesMatching(properties);
-		if (!files.isEmpty()) {
-			file = files.iterator().next();
+		ICMakeToolChainFile file = manager.getToolChainFileFor(toolChain);
+		if (file == null) {
+			Collection<ICMakeToolChainFile> files = manager.getToolChainFilesMatching(properties);
+			if (!files.isEmpty()) {
+				file = files.iterator().next();
+			}
 		}
 
 		// create config
diff --git a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/build/CBuildConfiguration.java b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/build/CBuildConfiguration.java
index c6137462782..f9222e48b46 100644
--- a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/build/CBuildConfiguration.java
+++ b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/build/CBuildConfiguration.java
@@ -554,7 +554,7 @@ public abstract class CBuildConfiguration extends PlatformObject
 	/**
 	 * @since 6.1
 	 */
-	protected void loadScannerInfoCache() {
+	protected synchronized void loadScannerInfoCache() {
 		if (scannerInfoCache == null) {
 			File cacheFile = getScannerInfoCacheFile();
 			if (cacheFile.exists()) {