diff --git a/src/plugins/cmakeprojectmanager/builddirmanager.cpp b/src/plugins/cmakeprojectmanager/builddirmanager.cpp
index 7114e136c6d..82cd4d36b2a 100644
--- a/src/plugins/cmakeprojectmanager/builddirmanager.cpp
+++ b/src/plugins/cmakeprojectmanager/builddirmanager.cpp
@@ -451,6 +451,14 @@ CMakeConfig BuildDirManager::parseConfiguration() const
             CMakeConfigItem::Type t = fromByteArray(type);
             if (t != CMakeConfigItem::INTERNAL)
                 result << CMakeConfigItem(key, t, documentation, value);
+
+            // Sanity checks:
+            if (key == "CMAKE_HOME_DIRECTORY") {
+                const Utils::FileName actualSourceDir = Utils::FileName::fromUserInput(QString::fromUtf8(value));
+                if (actualSourceDir != m_sourceDir)
+                    emit errorOccured(tr("Build directory contains a build of the wrong project (%1).")
+                                      .arg(actualSourceDir.toUserOutput()));
+            }
         }
     }
 
diff --git a/src/plugins/cmakeprojectmanager/builddirmanager.h b/src/plugins/cmakeprojectmanager/builddirmanager.h
index b67183ba884..8aafa5bfa8d 100644
--- a/src/plugins/cmakeprojectmanager/builddirmanager.h
+++ b/src/plugins/cmakeprojectmanager/builddirmanager.h
@@ -100,6 +100,7 @@ private:
 
     const Utils::FileName m_sourceDir;
     Utils::FileName m_buildDir;
+    Utils::FileName m_parsedSourceDir;
     const ProjectExplorer::Kit *const m_kit;
     Utils::Environment m_environment;
     CMakeConfig m_inputConfig;
diff --git a/src/plugins/cmakeprojectmanager/cmakebuildconfiguration.cpp b/src/plugins/cmakeprojectmanager/cmakebuildconfiguration.cpp
index 866ba8a992b..0d554ff4dd7 100644
--- a/src/plugins/cmakeprojectmanager/cmakebuildconfiguration.cpp
+++ b/src/plugins/cmakeprojectmanager/cmakebuildconfiguration.cpp
@@ -81,6 +81,16 @@ CMakeBuildConfiguration::CMakeBuildConfiguration(ProjectExplorer::Target *parent
                                            displayName(), BuildConfiguration::Unknown));
 }
 
+bool CMakeBuildConfiguration::isEnabled() const
+{
+    return m_error.isEmpty();
+}
+
+QString CMakeBuildConfiguration::disabledReason() const
+{
+    return error();
+}
+
 CMakeBuildConfiguration::CMakeBuildConfiguration(ProjectExplorer::Target *parent,
                                                  CMakeBuildConfiguration *source) :
     BuildConfiguration(parent, source),
@@ -160,6 +170,20 @@ CMakeConfig CMakeBuildConfiguration::cmakeConfiguration() const
     return m_configuration;
 }
 
+void CMakeBuildConfiguration::setError(const QString &message)
+{
+    if (m_error == message)
+        return;
+    m_error = message;
+    emit enabledChanged();
+    emit errorOccured(m_error);
+}
+
+QString CMakeBuildConfiguration::error() const
+{
+    return m_error;
+}
+
 ProjectExplorer::NamedWidget *CMakeBuildConfiguration::createConfigWidget()
 {
     return new CMakeBuildSettingsWidget(this);
diff --git a/src/plugins/cmakeprojectmanager/cmakebuildconfiguration.h b/src/plugins/cmakeprojectmanager/cmakebuildconfiguration.h
index 85031f9388a..ff5eb0b87f9 100644
--- a/src/plugins/cmakeprojectmanager/cmakebuildconfiguration.h
+++ b/src/plugins/cmakeprojectmanager/cmakebuildconfiguration.h
@@ -48,6 +48,9 @@ class CMakeBuildConfiguration : public ProjectExplorer::BuildConfiguration
 public:
     CMakeBuildConfiguration(ProjectExplorer::Target *parent);
 
+    bool isEnabled() const override;
+    QString disabledReason() const override;
+
     ProjectExplorer::NamedWidget *createConfigWidget() override;
 
     QVariantMap toMap() const override;
@@ -59,6 +62,12 @@ public:
     void setCMakeConfiguration(const CMakeConfig &config);
     CMakeConfig cmakeConfiguration() const;
 
+    void setError(const QString &message);
+    QString error() const;
+
+signals:
+    void errorOccured(const QString &message);
+
 protected:
     CMakeBuildConfiguration(ProjectExplorer::Target *parent, CMakeBuildConfiguration *source);
     bool fromMap(const QVariantMap &map) override;
@@ -66,6 +75,7 @@ protected:
 private:
     QString m_initialArguments;
     CMakeConfig m_configuration;
+    QString m_error;
 
     friend class CMakeProjectManager::CMakeProject;
 };
diff --git a/src/plugins/cmakeprojectmanager/cmakebuildsettingswidget.cpp b/src/plugins/cmakeprojectmanager/cmakebuildsettingswidget.cpp
index d85ef176ef4..2a348a82883 100644
--- a/src/plugins/cmakeprojectmanager/cmakebuildsettingswidget.cpp
+++ b/src/plugins/cmakeprojectmanager/cmakebuildsettingswidget.cpp
@@ -29,6 +29,7 @@
 #include "cmakeproject.h"
 #include "cmakebuildconfiguration.h"
 
+#include <coreplugin/coreicons.h>
 #include <coreplugin/icore.h>
 #include <coreplugin/find/itemviewfind.h>
 #include <projectexplorer/projectexplorer.h>
@@ -94,7 +95,21 @@ CMakeBuildSettingsWidget::CMakeBuildSettingsWidget(CMakeBuildConfiguration *bc)
     mainLayout->addWidget(buildDirChooser->buttonAtIndex(0), row, 2);
 
     ++row;
-    mainLayout->addItem(new QSpacerItem(20, 20), row, 0);
+    mainLayout->addItem(new QSpacerItem(20, 10), row, 0);
+
+    ++row;
+    m_errorLabel = new QLabel;
+    m_errorLabel->setPixmap(Core::Icons::ERROR.pixmap());
+    m_errorLabel->setVisible(false);
+    m_errorMessageLabel = new QLabel;
+    m_errorMessageLabel->setVisible(false);
+    auto boxLayout = new QHBoxLayout;
+    boxLayout->addWidget(m_errorLabel);
+    boxLayout->addWidget(m_errorMessageLabel);
+    mainLayout->addLayout(boxLayout, row, 0, 1, 3, Qt::AlignHCenter);
+
+    ++row;
+    mainLayout->addItem(new QSpacerItem(20, 10), row, 0);
 
     ++row;
     auto tree = new Utils::TreeView;
@@ -145,6 +160,7 @@ CMakeBuildSettingsWidget::CMakeBuildSettingsWidget(CMakeBuildConfiguration *bc)
     mainLayout->addWidget(m_reconfigureButton, row, 0, 1, 3);
 
     updateAdvancedCheckBox();
+    setError(bc->error());
 
     connect(project, &CMakeProject::parsingStarted, this, [this]() {
         updateButtonState();
@@ -180,6 +196,24 @@ CMakeBuildSettingsWidget::CMakeBuildSettingsWidget(CMakeBuildConfiguration *bc)
         m_configView->setCurrentIndex(idx);
         m_configView->edit(idx);
     });
+
+    connect(bc, &CMakeBuildConfiguration::errorOccured, this, &CMakeBuildSettingsWidget::setError);
+}
+
+void CMakeBuildSettingsWidget::setError(const QString &message)
+{
+    bool showWarning = !message.isEmpty();
+    m_errorLabel->setVisible(showWarning);
+    m_errorLabel->setToolTip(message);
+    m_errorMessageLabel->setVisible(showWarning);
+    m_errorMessageLabel->setText(message);
+    m_errorMessageLabel->setToolTip(message);
+
+    m_configView->setVisible(!showWarning);
+    m_editButton->setVisible(!showWarning);
+    m_resetButton->setVisible(!showWarning);
+    m_showAdvancedCheckBox->setVisible(!showWarning);
+    m_reconfigureButton->setVisible(!showWarning);
 }
 
 void CMakeBuildSettingsWidget::updateButtonState()
diff --git a/src/plugins/cmakeprojectmanager/cmakebuildsettingswidget.h b/src/plugins/cmakeprojectmanager/cmakebuildsettingswidget.h
index 341781b9784..af09ac323e5 100644
--- a/src/plugins/cmakeprojectmanager/cmakebuildsettingswidget.h
+++ b/src/plugins/cmakeprojectmanager/cmakebuildsettingswidget.h
@@ -33,6 +33,7 @@
 
 QT_BEGIN_NAMESPACE
 class QCheckBox;
+class QLabel;
 class QPushButton;
 class QTreeView;
 class QSortFilterProxyModel;
@@ -52,6 +53,8 @@ class CMakeBuildSettingsWidget : public ProjectExplorer::NamedWidget
 public:
     CMakeBuildSettingsWidget(CMakeBuildConfiguration *bc);
 
+    void setError(const QString &message);
+
 private:
     void updateButtonState();
     void updateAdvancedCheckBox();
@@ -66,6 +69,8 @@ private:
     QCheckBox *m_showAdvancedCheckBox;
     QPushButton *m_reconfigureButton;
     QTimer m_showProgressTimer;
+    QLabel *m_errorLabel;
+    QLabel *m_errorMessageLabel;
 };
 
 } // namespace Internal
diff --git a/src/plugins/cmakeprojectmanager/cmakeproject.cpp b/src/plugins/cmakeprojectmanager/cmakeproject.cpp
index 88b30838a17..86da5cb5c3b 100644
--- a/src/plugins/cmakeprojectmanager/cmakeproject.cpp
+++ b/src/plugins/cmakeprojectmanager/cmakeproject.cpp
@@ -139,6 +139,8 @@ void CMakeProject::changeActiveBuildConfiguration(ProjectExplorer::BuildConfigur
                 this, &CMakeProject::parsingStarted);
         connect(m_buildDirManager, &BuildDirManager::dataAvailable,
                 this, &CMakeProject::parseCMakeOutput);
+        connect(m_buildDirManager, &BuildDirManager::errorOccured,
+                cmakebc, &CMakeBuildConfiguration::setError);
     }
 }