diff --git a/tycho-compiler-jdt/src/main/java/org/eclipse/tycho/compiler/jdt/JDTCompiler.java b/tycho-compiler-jdt/src/main/java/org/eclipse/tycho/compiler/jdt/JDTCompiler.java
index 5ef9838584..5fc0b9cef3 100644
--- a/tycho-compiler-jdt/src/main/java/org/eclipse/tycho/compiler/jdt/JDTCompiler.java
+++ b/tycho-compiler-jdt/src/main/java/org/eclipse/tycho/compiler/jdt/JDTCompiler.java
@@ -110,6 +110,9 @@ public CompilerResult performCompile(CompilerConfiguration config) throws Compil
         if (sourceFiles.length == 0) {
             return new CompilerResult();
         }
+        //even though order of java sources should not matter, it can make a difference sometimes (e.g. lamda numbering) see https://github.com/eclipse-jdt/eclipse.jdt.core/issues/1921
+        //so to have always the same arguments regardless of hash table ordering that is used internally by plexus compiler we sort the files simply by name
+        Arrays.sort(sourceFiles);
 
         logger.info("Compiling " + sourceFiles.length + " " + "source file" + (sourceFiles.length == 1 ? "" : "s")
                 + " to " + destinationDir.getAbsolutePath() + " using " + COMPILER_NAME + "");