diff --git a/language/backgroundparser/parsejob.cpp b/language/backgroundparser/parsejob.cpp
--- a/language/backgroundparser/parsejob.cpp
+++ b/language/backgroundparser/parsejob.cpp
@@ -42,6 +42,7 @@
 #include "duchain/parsingenvironment.h"
 
 #include <util/foregroundlock.h>
+#include <util/kdevstringhandler.h>
 #include <interfaces/icore.h>
 #include <interfaces/ilanguagecontroller.h>
 #include <codegen/coderepresentation.h>
@@ -314,6 +315,9 @@
         }
 
         d->contents.contents = file.readAll(); ///@todo Convert from local encoding to utf-8 if they don't match
+
+        // This is consistent with KTextEditor::Document::text() as used for already-open files.
+        normalizeLineEndings(d->contents.contents);
         d->contents.modification = KDevelop::ModificationRevision(lastModified);
 
         file.close();
diff --git a/util/kdevstringhandler.h b/util/kdevstringhandler.h
--- a/util/kdevstringhandler.h
+++ b/util/kdevstringhandler.h
@@ -23,6 +23,7 @@
 #include "utilexport.h"
 
 class QString;
+class QByteArray;
 class QChar;
 class QStringList;
 class QVariant;
@@ -66,6 +67,10 @@
      */
     KDEVPLATFORMUTIL_EXPORT QString stripAnsiSequences(const QString& str);
 
+    /**
+     * Replace all occurrences of '\r' or '\r\n' in @p text with '\n'.
+     */
+    KDEVPLATFORMUTIL_EXPORT void normalizeLineEndings(QByteArray& text);
 }
 
 #endif // KDEVPLATFORM_KDEVSTRINGHANDLER_H
diff --git a/util/kdevstringhandler.cpp b/util/kdevstringhandler.cpp
--- a/util/kdevstringhandler.cpp
+++ b/util/kdevstringhandler.cpp
@@ -66,6 +66,7 @@
 
 #include <QStringList>
 #include <QString>
+#include <QByteArray>
 #include <QChar>
 #include <QDataStream>
 #include <QVariant>
@@ -229,3 +230,16 @@
     }
     return result;
 }
+
+void KDevelop::normalizeLineEndings(QByteArray& text)
+{
+    for (int i = 0, s = text.size(); i < s; ++i) {
+        if (text[i] != '\r') {
+            continue;
+        } else if (i + 1 < s && text[i + 1] == '\n') {
+            text.remove(i, 1);
+        } else {
+            text[i] = '\n';
+        }
+    }
+}
diff --git a/util/tests/test_stringhandler.h b/util/tests/test_stringhandler.h
--- a/util/tests/test_stringhandler.h
+++ b/util/tests/test_stringhandler.h
@@ -34,6 +34,9 @@
 
     void testStripAnsiSequences();
     void testStripAnsiSequences_data();
+
+    void testNormalizeLineEndings();
+    void testNormalizeLineEndings_data();
 };
 
 #endif // TESTSTRINGHANDLER_H
diff --git a/util/tests/test_stringhandler.cpp b/util/tests/test_stringhandler.cpp
--- a/util/tests/test_stringhandler.cpp
+++ b/util/tests/test_stringhandler.cpp
@@ -72,4 +72,32 @@
     QTest::newRow("simple")
         << QStringLiteral("foo bar:")
         << "foo bar:";
-}
\ No newline at end of file
+}
+
+void TestStringHandler::testNormalizeLineEndings()
+{
+    QFETCH(QByteArray, text);
+    QFETCH(QByteArray, expectedOutput);
+
+    normalizeLineEndings(text);
+    QCOMPARE(text, expectedOutput);
+}
+
+void TestStringHandler::testNormalizeLineEndings_data()
+{
+    QTest::addColumn<QByteArray>("text");
+    QTest::addColumn<QByteArray>("expectedOutput");
+
+    QTest::newRow("trivial")
+        << QByteArray("foo\nbar\n")
+        << QByteArray("foo\nbar\n");
+    QTest::newRow("dos")
+        << QByteArray("foo\r\nbar\r\n")
+        << QByteArray("foo\nbar\n");
+    QTest::newRow("macos_classic")
+        << QByteArray("foo\rbar\r")
+        << QByteArray("foo\nbar\n");
+    QTest::newRow("mess")
+        << QByteArray("\r\n\n\r\r\r\n\r")
+        << QByteArray("\n\n\n\n\n\n");
+}