diff --git a/src/main/java/dk/camelot64/kickc/Compiler.java b/src/main/java/dk/camelot64/kickc/Compiler.java
index 688115fcf..00c68057c 100644
--- a/src/main/java/dk/camelot64/kickc/Compiler.java
+++ b/src/main/java/dk/camelot64/kickc/Compiler.java
@@ -33,6 +33,9 @@ public class Compiler {
     * Currently the optimization is flaky and results in NPE's and wrong values in some programs. */
    private boolean enableLoopHeadConstant = false;
 
+   /** Missing fragments produce a warning instead of an error */
+   private boolean warnFragmentMissing = false;
+
    /** File name of link script to use (from command line parameter). */
    private String linkScriptFileName;
 
@@ -40,6 +43,14 @@ public class Compiler {
       this.program = new Program();
    }
 
+   public boolean isWarnFragmentMissing() {
+      return warnFragmentMissing;
+   }
+
+   public void setWarnFragmentMissing(boolean warnFragmentMissing) {
+      this.warnFragmentMissing = warnFragmentMissing;
+   }
+
    public void setLinkScriptFileName(String linkScript) {
       linkScriptFileName = linkScript;
    }
@@ -475,7 +486,7 @@ public class Compiler {
       new Pass4RegistersFinalize(program).allocate(true);
 
       // Initial Code generation
-      new Pass4CodeGeneration(program, false).generate();
+      new Pass4CodeGeneration(program, false, warnFragmentMissing).generate();
       new Pass4AssertNoCpuClobber(program).check();
       getLog().append("\nINITIAL ASM");
       getLog().append("Target platform is " + program.getTargetPlatform().getName());
@@ -521,7 +532,7 @@ public class Compiler {
 
       // Final ASM code generation before optimization
       program.clearPhiTransitions();
-      new Pass4CodeGeneration(program, false).generate();
+      new Pass4CodeGeneration(program, false, warnFragmentMissing).generate();
       new Pass4AssertNoCpuClobber(program).check();
 
       // Remove unnecessary register savings from interrupts {@link InterruptType#HARDWARE_NOCLOBBER}
diff --git a/src/main/java/dk/camelot64/kickc/KickC.java b/src/main/java/dk/camelot64/kickc/KickC.java
index 294bd757b..375b6ea01 100644
--- a/src/main/java/dk/camelot64/kickc/KickC.java
+++ b/src/main/java/dk/camelot64/kickc/KickC.java
@@ -111,6 +111,9 @@ public class KickC implements Callable<Void> {
    @CommandLine.Option(names = {"-vasmoptimize"}, description = "Verbosity Option. Assembler optimization.")
    private boolean verboseAsmOptimize = false;
 
+   @CommandLine.Option(names = {"-Wfragment"}, description = "Warning Option. Missing fragments produces a warning instead of an error.")
+   private boolean warnFragmentMissing = false;
+
    @CommandLine.Option(names = {"-fragment"}, description = "Print the ASM code for a named fragment. The fragment is loaded/synthesized and the ASM variations are written to the output.")
    private String fragment = null;
 
@@ -227,6 +230,10 @@ public class KickC implements Callable<Void> {
             compiler.disableLoopHeadConstant();
          }
 
+         if(warnFragmentMissing) {
+            compiler.setWarnFragmentMissing(true);
+         }
+
          if(linkScript!=null) {
             compiler.setLinkScriptFileName(linkScript);
          }
diff --git a/src/main/java/dk/camelot64/kickc/model/LiveRangeVariables.java b/src/main/java/dk/camelot64/kickc/model/LiveRangeVariables.java
index a5092a3a8..8e0f0134d 100644
--- a/src/main/java/dk/camelot64/kickc/model/LiveRangeVariables.java
+++ b/src/main/java/dk/camelot64/kickc/model/LiveRangeVariables.java
@@ -78,5 +78,10 @@ public class LiveRangeVariables {
       return liveRanges.get(variable);
    }
 
+   public int size() {
+      return liveRanges.size();
+
+   }
+
 
 }
diff --git a/src/main/java/dk/camelot64/kickc/passes/Pass4CodeGeneration.java b/src/main/java/dk/camelot64/kickc/passes/Pass4CodeGeneration.java
index 7482d5d03..15bb92551 100644
--- a/src/main/java/dk/camelot64/kickc/passes/Pass4CodeGeneration.java
+++ b/src/main/java/dk/camelot64/kickc/passes/Pass4CodeGeneration.java
@@ -25,6 +25,9 @@ public class Pass4CodeGeneration {
    /** Should the generated ASM contain verbose alive info for the statements (costs a bit more to generate). */
    boolean verboseAliveInfo;
 
+   /** Missing fragments produce a warning instead of an error. */
+   boolean warnFragmentMissing;
+
    /** The program being generated. */
    private Program program;
 
@@ -57,9 +60,10 @@ public class Pass4CodeGeneration {
       transitionsGenerated.put(transition, Boolean.TRUE);
    }
 
-   public Pass4CodeGeneration(Program program, boolean verboseAliveInfo) {
+   public Pass4CodeGeneration(Program program, boolean verboseAliveInfo, boolean warnFragmentMissing) {
       this.program = program;
       this.verboseAliveInfo = verboseAliveInfo;
+      this.warnFragmentMissing = warnFragmentMissing;
    }
 
    ControlFlowGraph getGraph() {
@@ -644,7 +648,12 @@ public class Pass4CodeGeneration {
             try {
                generateStatementAsm(asm, block, statement, aluState, true);
             } catch(AsmFragmentTemplateSynthesizer.UnknownFragmentException e) {
-               throw new CompileError("Unknown fragment for statement " + statement.toString(program, false) + "\nMissing ASM fragment " + e.getFragmentSignature(), statement.getSource());
+               if(warnFragmentMissing) {
+                  program.getLog().append("Warning! Unknown fragment for statement " + statement.toString(program, false) + "\nMissing ASM fragment " + e.getFragmentSignature()+"\n"+statement.getSource().toString());
+                  asm.addLine(new AsmInlineKickAsm(".assert \"Missing ASM fragment "+ e.getFragmentSignature()+"\", 0, 1", 0L, 0L));
+               }  else {
+                  throw new CompileError("Unknown fragment for statement " + statement.toString(program, false) + "\nMissing ASM fragment " + e.getFragmentSignature(), statement.getSource());
+               }
             }
          }
       }
diff --git a/src/main/java/dk/camelot64/kickc/passes/Pass4RegisterUpliftCombinations.java b/src/main/java/dk/camelot64/kickc/passes/Pass4RegisterUpliftCombinations.java
index 4684cb337..b2c62e678 100644
--- a/src/main/java/dk/camelot64/kickc/passes/Pass4RegisterUpliftCombinations.java
+++ b/src/main/java/dk/camelot64/kickc/passes/Pass4RegisterUpliftCombinations.java
@@ -110,7 +110,7 @@ public class Pass4RegisterUpliftCombinations extends Pass2Base {
       // Generate ASM
       try {
          program.clearPhiTransitions();
-         new Pass4CodeGeneration(program, false).generate();
+         new Pass4CodeGeneration(program, false, false).generate();
       } catch(AsmFragmentTemplateSynthesizer.UnknownFragmentException e) {
          unknownFragments.add(e.getFragmentSignature());
          if(program.getLog().isVerboseUplift()) {
diff --git a/src/main/java/dk/camelot64/kickc/passes/Pass4RegisterUpliftPotentialRegisterAnalysis.java b/src/main/java/dk/camelot64/kickc/passes/Pass4RegisterUpliftPotentialRegisterAnalysis.java
index d13d54c9e..c5a6be49a 100644
--- a/src/main/java/dk/camelot64/kickc/passes/Pass4RegisterUpliftPotentialRegisterAnalysis.java
+++ b/src/main/java/dk/camelot64/kickc/passes/Pass4RegisterUpliftPotentialRegisterAnalysis.java
@@ -163,7 +163,7 @@ public class Pass4RegisterUpliftPotentialRegisterAnalysis extends Pass2Base {
          asm.startChunk(block.getScope(), statement.getIndex(), statement.toString(getProgram(), false));
          Pass4CodeGeneration.AsmCodegenAluState aluState = new Pass4CodeGeneration.AsmCodegenAluState();
          try {
-            (new Pass4CodeGeneration(getProgram(), false)).generateStatementAsm(asm, block, statement, aluState, false);
+            (new Pass4CodeGeneration(getProgram(), false, false)).generateStatementAsm(asm, block, statement, aluState, false);
          } catch(AsmFragmentTemplateSynthesizer.UnknownFragmentException e) {
             unknownFragments.add(e.getFragmentSignature());
             StringBuilder msg = new StringBuilder();
diff --git a/src/main/java/dk/camelot64/kickc/passes/calcs/PassNCalcLiveRangeVariables.java b/src/main/java/dk/camelot64/kickc/passes/calcs/PassNCalcLiveRangeVariables.java
index 3a987986c..901fc228b 100644
--- a/src/main/java/dk/camelot64/kickc/passes/calcs/PassNCalcLiveRangeVariables.java
+++ b/src/main/java/dk/camelot64/kickc/passes/calcs/PassNCalcLiveRangeVariables.java
@@ -40,14 +40,11 @@ public class PassNCalcLiveRangeVariables extends PassNCalcBase<LiveRangeVariable
 
    /** Variables referenced inside each procedure and all it's sub-calls. */
    private Map<ProcedureRef, Collection<VariableRef>> procedureReferencedVars;
-   
-   static int callCount = 0;
 
    /**
     * Calculate the variables referenced inside each procedure and all it's sub-calls.
     */
    private void calculateProcedureReferencedVars() {
-      //getLog().append("calculateLiveRanges starting "+callCount);
       VariableReferenceInfos referenceInfo = getProgram().getVariableReferenceInfos();
       Collection<Procedure> allProcedures = getScope().getAllProcedures(true);
       Map<ProcedureRef, Collection<VariableRef>> procReferencedVars = new LinkedHashMap<>();
@@ -55,8 +52,6 @@ public class PassNCalcLiveRangeVariables extends PassNCalcBase<LiveRangeVariable
          Collection<VariableRef> referencedVars = referenceInfo.getReferencedVars(procedure.getRef().getLabelRef());
          procReferencedVars.put(procedure.getRef(), referencedVars);
       }
-      //getLog().append("calculateLiveRanges done "+callCount);
-      callCount++;
       this.procedureReferencedVars = procReferencedVars;
    }
 
@@ -83,9 +78,7 @@ public class PassNCalcLiveRangeVariables extends PassNCalcBase<LiveRangeVariable
     * @return true if any live ranges was modified. false if no modification was performed (and the propagation is complete)
     */
    private boolean calculateLiveRanges(LiveRangeVariables liveRanges) {
-
       VariableReferenceInfos referenceInfo = getProgram().getVariableReferenceInfos();
-
       boolean modified = false;
       for(ControlFlowBlock block : getProgram().getGraph().getAllBlocks()) {
          for(Statement stmt : block.getStatements()) {