diff --git a/packages/common/src/directives/ng_for_of.ts b/packages/common/src/directives/ng_for_of.ts
index bae7bd543d..597937d327 100644
--- a/packages/common/src/directives/ng_for_of.ts
+++ b/packages/common/src/directives/ng_for_of.ts
@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {Directive, DoCheck, EmbeddedViewRef, Input, isDevMode, IterableChangeRecord, IterableChanges, IterableDiffer, IterableDiffers, NgIterable, TemplateRef, TrackByFunction, ViewContainerRef} from '@angular/core';
+import {Directive, DoCheck, EmbeddedViewRef, Input, IterableChangeRecord, IterableChanges, IterableDiffer, IterableDiffers, NgIterable, TemplateRef, TrackByFunction, ViewContainerRef} from '@angular/core';
 
 /**
  * @publicApi
@@ -159,7 +159,7 @@ export class NgForOf<T, U extends NgIterable<T> = NgIterable<T>> implements DoCh
    */
   @Input()
   set ngForTrackBy(fn: TrackByFunction<T>) {
-    if (isDevMode() && fn != null && typeof fn !== 'function') {
+    if ((typeof ngDevMode === 'undefined' || ngDevMode) && fn != null && typeof fn !== 'function') {
       // TODO(vicb): use a log service once there is a public one available
       if (<any>console && <any>console.warn) {
         console.warn(
diff --git a/packages/common/src/pipes/number_pipe.ts b/packages/common/src/pipes/number_pipe.ts
index edc6d08094..4c1c54ff55 100644
--- a/packages/common/src/pipes/number_pipe.ts
+++ b/packages/common/src/pipes/number_pipe.ts
@@ -241,7 +241,7 @@ export class CurrencyPipe implements PipeTransform {
     locale = locale || this._locale;
 
     if (typeof display === 'boolean') {
-      if (<any>console && <any>console.warn) {
+      if ((typeof ngDevMode === 'undefined' || ngDevMode) && <any>console && <any>console.warn) {
         console.warn(
             `Warning: the currency pipe has been changed in Angular v5. The symbolDisplay option (third parameter) is now a string instead of a boolean. The accepted values are "code", "symbol" or "symbol-narrow".`);
       }