Fix for the compiler path in compile_commands.json file

Compiler path was wrongly created when anything was set on the "Prefix"
option from "Cross Settings". The code needs to check if anything is set
there before creating the default path for the compiler.

Author: alicetrifu

build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/internal/core/jsoncdb/generator/CompilationDatabaseGenerator.java

@@ -31,9 +31,11 @@
 import org.eclipse.cdt.managedbuilder.core.IFolderInfo;
 import org.eclipse.cdt.managedbuilder.core.IManagedCommandLineGenerator;
 import org.eclipse.cdt.managedbuilder.core.IManagedCommandLineInfo;
+import org.eclipse.cdt.managedbuilder.core.IOption;
 import org.eclipse.cdt.managedbuilder.core.IOutputType;
 import org.eclipse.cdt.managedbuilder.core.IResourceInfo;
 import org.eclipse.cdt.managedbuilder.core.ITool;
+import org.eclipse.cdt.managedbuilder.core.IToolChain;
 import org.eclipse.cdt.managedbuilder.core.ManagedBuildManager;
 import org.eclipse.cdt.managedbuilder.core.jsoncdb.CompilationDatabaseInformation;
 import org.eclipse.cdt.managedbuilder.core.jsoncdb.ICompilationDatabaseContributor;
@@ -229,7 +231,7 @@ private List<CompilationDatabaseInformation> populateObjList(IProject project, I
 						outputLocation + "", inputStrings, sourceLocation, outputLocation); //$NON-NLS-1$
 
 				IBuildMacroProvider provider = ManagedBuildManager.getBuildMacroProvider();
-				String compilerName = CompilationDatabaseGenerator.getCompilerName(tool);
+				String compilerName = CompilationDatabaseGenerator.getCompilerName(tool, config);
 				String commandLine = cmdLInfo.getCommandLine();
 				commandLine = commandLine.replace(compilerName, "").trim(); //$NON-NLS-1$
 				String compilerPath = findCompilerInPath(tool, config);
@@ -442,7 +444,7 @@ private String findCompilerInPath(ITool tool, IConfiguration config) {
 		if (toolMap.containsKey(tool)) {
 			return "\"" + toolMap.get(tool) + "\""; //$NON-NLS-1$//$NON-NLS-2$
 		}
-		String compilerName = CompilationDatabaseGenerator.getCompilerName(tool);
+		String compilerName = CompilationDatabaseGenerator.getCompilerName(tool, config);
 		File pathToCompiler = new File(compilerName);
 
 		if (pathToCompiler.isAbsolute()) {
@@ -469,9 +471,14 @@ private String findCompilerInPath(ITool tool, IConfiguration config) {
 		return null;
 	}
 
-	private static String getCompilerName(ITool tool) {
+	private static String getCompilerName(ITool tool, IConfiguration config) {
+		IToolChain toolchain = config.getToolChain();
+		IOption option = toolchain.getOptionBySuperClassId("cdt.managedbuild.option.gnu.cross.prefix"); //$NON-NLS-1$
 		String compilerCommand = tool.getToolCommand();
 		String[] arguments = CommandLineUtil.argumentsToArray(compilerCommand);
+		if (!("").equals(option.getValue())) { //$NON-NLS-1$
+			return option.getValue() + arguments[0];
+		}
 		if (arguments.length == 0) {
 			return ""; //$NON-NLS-1$
 		}