diff --git a/src/worker/builder.ts b/src/worker/builder.ts
index 4b427541..51c7ec88 100644
--- a/src/worker/builder.ts
+++ b/src/worker/builder.ts
@@ -1,4 +1,4 @@
-import { getBasePlatform } from "../common/util";
+import { convertDataToUint8Array, getBasePlatform } from "../common/util";
 import { WorkerBuildStep, WorkerError, WorkerErrorResult, WorkerMessage, WorkerResult, WorkingStore } from "../common/workertypes";
 import { PLATFORM_PARAMS } from "./platforms";
 import { TOOLS } from "./workertools";
@@ -414,3 +414,20 @@ export function fixParamsWithDefines(path: string, params) {
     }
   }
 }
+
+export function processEmbedDirective(code: string) {
+  let re3 = /^\s*#embed\s+"(.+?)"/gm;
+  // find #embed "filename.bin" and replace with C array data
+  return code.replace(re3, (m, m1) => {
+      let filename = m1;
+      let filedata = store.getFileData(filename);
+      let bytes = convertDataToUint8Array(filedata);
+      if (!bytes) throw new Error('#embed: file not found: "' + filename + '"');
+      let out = '';
+      for (let i = 0; i < bytes.length; i++) {
+          out += bytes[i].toString() + ',';
+      }
+      return out.substring(0, out.length-1);
+  });
+}
+
diff --git a/src/worker/tools/cc65.ts b/src/worker/tools/cc65.ts
index 656512a5..a4d99f2f 100644
--- a/src/worker/tools/cc65.ts
+++ b/src/worker/tools/cc65.ts
@@ -1,7 +1,7 @@
 
-import { convertDataToUint8Array, getFilenamePrefix, getRootBasePlatform, safeident } from "../../common/util";
+import { getRootBasePlatform } from "../../common/util";
 import { CodeListingMap, WorkerError } from "../../common/workertypes";
-import { BuildStep, BuildStepResult, gatherFiles, staleFiles, populateFiles, fixParamsWithDefines, putWorkFile, populateExtraFiles, store, populateEntry, anyTargetChanged } from "../builder";
+import { BuildStep, BuildStepResult, gatherFiles, staleFiles, populateFiles, fixParamsWithDefines, putWorkFile, populateExtraFiles, store, populateEntry, anyTargetChanged, processEmbedDirective } from "../builder";
 import { re_crlf, makeErrorMatcher } from "../listingutils";
 import { loadNative, moduleInstFn, print_fn, setupFS, execMain, emglobal, EmscriptenModule } from "../wasmutils";
 
@@ -270,22 +270,6 @@ export function linkLD65(step: BuildStep): BuildStepResult {
     }
 }
 
-function processIncbin(code: string) {
-    let re3 = /^\s*#embed\s+"(.+?)"/gm;
-    // find #embed "filename.bin" and replace with C array data
-    return code.replace(re3, (m, m1) => {
-        let filename = m1;
-        let filedata = store.getFileData(filename);
-        let bytes = convertDataToUint8Array(filedata);
-        if (!bytes) throw new Error('#embed: file not found: "' + filename + '"');
-        let out = '';
-        for (let i = 0; i < bytes.length; i++) {
-            out += bytes[i].toString() + ',';
-        }
-        return out;
-    });
-}
-
 export function compileCC65(step: BuildStep): BuildStepResult {
     loadNative("cc65");
     var params = step.params;
@@ -321,7 +305,7 @@ export function compileCC65(step: BuildStep): BuildStepResult {
             mainFilePath: step.path,
             processFn: (path, code) => {
                 if (typeof code === 'string') {
-                    code = processIncbin(code);
+                    code = processEmbedDirective(code);
                 }
                 return code;
             }
diff --git a/src/worker/tools/mcpp.ts b/src/worker/tools/mcpp.ts
index ccc57614..e707a76f 100644
--- a/src/worker/tools/mcpp.ts
+++ b/src/worker/tools/mcpp.ts
@@ -1,5 +1,5 @@
 import { getBasePlatform } from "../../common/util";
-import { BuildStep, populateFiles, populateExtraFiles, errorResult } from "../builder";
+import { BuildStep, populateFiles, populateExtraFiles, errorResult, processEmbedDirective } from "../builder";
 import { makeErrorMatcher, extractErrors } from "../listingutils";
 import { PLATFORM_PARAMS } from "../platforms";
 import { load, print_fn, setupFS, execMain, emglobal, EmscriptenModule } from "../wasmutils";
@@ -24,7 +24,15 @@ export function preprocessMCPP(step: BuildStep, filesys: string) {
     });
     var FS = MCPP.FS;
     if (filesys) setupFS(FS, filesys);
-    populateFiles(step, FS);
+    populateFiles(step, FS, {
+        mainFilePath: step.path,
+        processFn: (path, code) => {
+            if (typeof code === 'string') {
+                code = processEmbedDirective(code);
+            }
+            return code;
+        }
+    });
     populateExtraFiles(step, FS, params.extra_compile_files);
     // TODO: make configurable by other compilers
     var args = [