diff --git a/src/libs/utils/filepath.cpp b/src/libs/utils/filepath.cpp
index 8948004d6f4..21be6ec9020 100644
--- a/src/libs/utils/filepath.cpp
+++ b/src/libs/utils/filepath.cpp
@@ -1001,9 +1001,7 @@ bool FilePath::endsWith(const QString &s) const
 */
 bool FilePath::startsWithDriveLetter() const
 {
-    if (needsDevice() || !HostOsInfo::isWindowsHost())
-        return false;
-    return m_path.size() >= 2 && isWindowsDriveLetter(m_path[0]) && m_path.at(1) == ':';
+    return !needsDevice() && m_path.size() >= 2 && isWindowsDriveLetter(m_path[0]) && m_path.at(1) == ':';
 }
 
 /*!
diff --git a/src/plugins/docker/dockerdevice.cpp b/src/plugins/docker/dockerdevice.cpp
index 68d0ee8866d..c442a6593e3 100644
--- a/src/plugins/docker/dockerdevice.cpp
+++ b/src/plugins/docker/dockerdevice.cpp
@@ -636,7 +636,7 @@ QString DockerDevice::mapToDevicePath(const Utils::FilePath &globalPath) const
     // C:/dev/src -> /c/dev/src
     const FilePath normalized = FilePath::fromString(globalPath.path()).normalizedPathName();
     QString path = normalized.path();
-    if (normalized.startsWithDriveLetter()) {
+    if (HostOsInfo::isWindowsHost() && normalized.startsWithDriveLetter()) {
         const QChar lowerDriveLetter = path.at(0).toLower();
         path = '/' + lowerDriveLetter + path.mid(2); // strip C:
     }
diff --git a/src/plugins/projectexplorer/buildaspects.cpp b/src/plugins/projectexplorer/buildaspects.cpp
index bf6564614fb..5f80e50eabb 100644
--- a/src/plugins/projectexplorer/buildaspects.cpp
+++ b/src/plugins/projectexplorer/buildaspects.cpp
@@ -113,7 +113,7 @@ void BuildDirectoryAspect::addToLayout(LayoutBuilder &builder)
 
 FilePath BuildDirectoryAspect::fixupDir(const FilePath &dir)
 {
-    if (!dir.startsWithDriveLetter())
+    if (HostOsInfo::isWindowsHost() && !dir.startsWithDriveLetter())
         return {};
     const QString dirString = dir.toString().toLower();
     const QStringList drives = Utils::transform(QDir::drives(), [](const QFileInfo &fi) {
diff --git a/tests/auto/utils/fileutils/tst_fileutils.cpp b/tests/auto/utils/fileutils/tst_fileutils.cpp
index 1fa834a7017..ef375913fcd 100644
--- a/tests/auto/utils/fileutils/tst_fileutils.cpp
+++ b/tests/auto/utils/fileutils/tst_fileutils.cpp
@@ -789,9 +789,6 @@ void tst_fileutils::asyncLocalCopy()
 
 void tst_fileutils::startsWithDriveLetter_data()
 {
-    if (!HostOsInfo::isWindowsHost())
-        QSKIP("This test is only relevant on Windows");
-
     QTest::addColumn<FilePath>("path");
     QTest::addColumn<bool>("expected");