diff --git a/src/plugins/cpptools/headerpathfilter.cpp b/src/plugins/cpptools/headerpathfilter.cpp
index b656f8e136e..c7265e40444 100644
--- a/src/plugins/cpptools/headerpathfilter.cpp
+++ b/src/plugins/cpptools/headerpathfilter.cpp
@@ -71,15 +71,10 @@ void HeaderPathFilter::removeGccInternalIncludePaths()
         return;
 
     const Utils::FilePath gccInstallDir = projectPart.toolChainInstallDir;
-    auto isGccInternalInclude = [gccInstallDir](const HeaderPath &headerPath){
-        const auto includePath = Utils::FilePath::fromString(headerPath.path);
-        if (includePath.isChildOf(gccInstallDir)) {
-           const QString remainingPath = headerPath.path.mid(gccInstallDir.toString().size());
-           // MinGW ships the standard library headers in "<installdir>/include/c++".
-           // Ensure that we do not remove include paths pointing there.
-           return !remainingPath.startsWith("/include/c++");
-        }
-        return false;
+    auto isGccInternalInclude = [gccInstallDir](const HeaderPath &headerPath) {
+        const auto filePath = Utils::FilePath::fromString(headerPath.path);
+        return filePath == gccInstallDir.pathAppended("include")
+               || filePath == gccInstallDir.pathAppended("include-fixed");
     };
 
     Utils::erase(builtInHeaderPaths, isGccInternalInclude);
diff --git a/tests/unit/unittest/headerpathfilter-test.cpp b/tests/unit/unittest/headerpathfilter-test.cpp
index da9d735f49d..b5589e8ec35 100644
--- a/tests/unit/unittest/headerpathfilter-test.cpp
+++ b/tests/unit/unittest/headerpathfilter-test.cpp
@@ -245,7 +245,8 @@ TEST_F(HeaderPathFilter, ClangHeadersAndCppIncludesPathsOrderLinux)
                             HasBuiltIn("/builtin_path")));
 }
 
-// Include paths below the installation dir should be removed as they confuse clang.
+// GCC-internal include paths like <installdir>/include and <installdir/include-next> might confuse
+// clang and should be filtered out. clang on the command line filters them out, too.
 TEST_F(HeaderPathFilter, RemoveGccInternalPaths)
 {
     projectPart.toolChainInstallDir = Utils::FilePath::fromUtf8("/usr/lib/gcc/x86_64-linux-gnu/7");
@@ -264,7 +265,8 @@ TEST_F(HeaderPathFilter, RemoveGccInternalPaths)
     ASSERT_THAT(filter.builtInHeaderPaths, ElementsAre(HasBuiltIn(CLANG_RESOURCE_DIR)));
 }
 
-// MinGW ships the standard library headers in "<installdir>/include/c++".
+// Some distributions ship the standard library headers in "<installdir>/include/c++" (MinGW)
+// or e.g. "<installdir>/include/g++-v8" (Gentoo).
 // Ensure that we do not remove include paths pointing there.
 TEST_F(HeaderPathFilter, RemoveGccInternalPathsExceptForStandardPaths)
 {