diff --git a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/language/settings/providers/AbstractBuiltinSpecsDetector.java b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/language/settings/providers/AbstractBuiltinSpecsDetector.java
index 387e07ea8c8..d6feb81fd49 100644
--- a/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/language/settings/providers/AbstractBuiltinSpecsDetector.java
+++ b/build/org.eclipse.cdt.managedbuilder.core/src/org/eclipse/cdt/managedbuilder/language/settings/providers/AbstractBuiltinSpecsDetector.java
@@ -326,9 +326,9 @@ public abstract class AbstractBuiltinSpecsDetector extends AbstractLanguageSetti
 
 	@Override
 	protected URI getBuildDirURI(URI mappedRootURI) {
-		// Do not calculate buildDirURI for each line
 		if (buildDirURI == null) {
-			buildDirURI = super.getBuildDirURI(mappedRootURI);
+			// do not use build directory from MBS which could be not-existent when the provider runs
+			buildDirURI = currentProject != null ? currentProject.getLocationURI() : null;
 		}
 		return buildDirURI;
 	}
@@ -353,7 +353,7 @@ public abstract class AbstractBuiltinSpecsDetector extends AbstractLanguageSetti
 		super.startup(cfgDescription, cwdTracker);
 
 		mappedRootURI = null;
-		buildDirURI = super.getBuildDirURI(mappedRootURI);
+		buildDirURI = getBuildDirURI(mappedRootURI);
 	}
 
 	@Override
diff --git a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/CCorePlugin.java b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/CCorePlugin.java
index 42387484aef..22a22903a2e 100644
--- a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/CCorePlugin.java
+++ b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/CCorePlugin.java
@@ -1331,6 +1331,34 @@ public class CCorePlugin extends Plugin {
 		log(createStatus(e));
 	}
 
+	/**
+	 * Print a message in the log
+	 * 
+	 * @param severity - desired severity of the message in the log,
+	 *    one of {@link IStatus#INFO}, {@link IStatus#WARNING} or {@link IStatus#ERROR}
+	 * @param msg - message
+	 * 
+	 * @since 5.5
+	 * @noreference This method is not intended to be referenced by clients.
+	 */
+	public static void log(int severity, String msg) {
+		log(new Status(severity, PLUGIN_ID, msg));
+	}
+	
+	/**
+	 * Print a message in the log accompanied by stack trace
+	 * 
+	 * @param severity - desired severity of the message in the log,
+	 *    one of {@link IStatus#INFO}, {@link IStatus#WARNING} or {@link IStatus#ERROR}
+	 * @param msg - message
+	 * 
+	 * @since 5.5
+	 * @noreference This method is not intended to be referenced by clients.
+	 */
+	public static void logStackTrace(int severity, String msg) {
+		log(new Status(severity, PLUGIN_ID, msg, new Exception()));
+	}
+	
 	/**
 	 * @noreference This method is not intended to be referenced by clients.
 	 */
diff --git a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/CommandLauncher.java b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/CommandLauncher.java
index a5e0555717e..b93f723cb34 100644
--- a/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/CommandLauncher.java
+++ b/core/org.eclipse.cdt.core/src/org/eclipse/cdt/core/CommandLauncher.java
@@ -25,6 +25,7 @@ import org.eclipse.core.resources.IProject;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.IProgressMonitor;
+import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.osgi.util.NLS;
 
@@ -184,6 +185,10 @@ public class CommandLauncher implements ICommandLauncher {
 		}
 
 		File dir = workingDirectory != null ? workingDirectory.toFile() : null;
+		if (dir != null && !dir.isDirectory()) {
+			CCorePlugin.logStackTrace(IStatus.ERROR, NLS.bind(Messages.CommandLauncher_InvalidWorkingDirectory, dir));
+			dir = null;
+		}
 
 		try {
 			fProcess = ProcessFactory.getFactory().exec(fCommandArgs, env, dir);
diff --git a/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/internal/core/Messages.java b/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/internal/core/Messages.java
index 56fead20b7e..c63c806cecb 100644
--- a/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/internal/core/Messages.java
+++ b/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/internal/core/Messages.java
@@ -17,6 +17,7 @@ public class Messages extends NLS {
 	public static String Util_unexpectedError;
 	public static String Addr_valueOutOfRange;
 	public static String CommandLauncher_CommandCancelled;
+	public static String CommandLauncher_InvalidWorkingDirectory;
 	public static String CommandLauncher_ProgramNotFoundInPath;
 	public static String convention_illegalIdentifier;
 	public static String convention_invalid;
diff --git a/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/internal/core/messages.properties b/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/internal/core/messages.properties
index 9c51cb755e7..0dcb682ba7b 100644
--- a/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/internal/core/messages.properties
+++ b/core/org.eclipse.cdt.core/utils/org/eclipse/cdt/internal/core/messages.properties
@@ -48,6 +48,7 @@ Util_unexpectedError=Unexpected error
 
 Addr_valueOutOfRange=Address is outside valid range.
 CommandLauncher_CommandCancelled=Command canceled
+CommandLauncher_InvalidWorkingDirectory=Launch attempt in non existent working directory "{0}"
 CommandLauncher_ProgramNotFoundInPath=Error: Program "{0}" not found in PATH
 
 XmlUtil_InternalErrorLoading=Internal error while trying to load XML document