Dear R8 team,

After the update to AGP 7.1.2, our App Size increased by 5% (caused by the dex files size increase of 17.3%).

Checked out your code, compile and try on the project. I figured out the dex file size spike caused by this commit https://r8-review.googlesource.com/c/r8/+/61680

In an early investigation of the dex files:

The number of Classes increased from 126812 to 129056

The number of Methods increased from 644636 to 644981

References Methods reduced from 730370 to 729775

There are a lot more lambda classes is keeping in the dex files after applying the commit to R8. For example:

.class public final synthetic Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler$$ExternalSyntheticLambda1;
.super Ljava/lang/Object;
.source "SourceFile"

# interfaces
.implements Lcom/google/android/datatransport/runtime/synchronization/SynchronizationGuard$CriticalSection;


# instance fields
.field public final synthetic com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.f$0:Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler;

.field public final synthetic com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.f$1:Lcom/google/android/datatransport/runtime/TransportContext;

.field public final synthetic com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.f$2:Lcom/google/android/datatransport/runtime/EventInternal;


# direct methods
.method public synthetic constructor com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.<init>(Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler;Lcom/google/android/datatransport/runtime/TransportContext;Lcom/google/android/datatransport/runtime/EventInternal;)V
    .registers 4

    invoke-direct {p0}, Ljava/lang/Object;-><init>()V

    iput-object p1, p0, Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler$$ExternalSyntheticLambda1;->com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.f$0:Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler;

    iput-object p2, p0, Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler$$ExternalSyntheticLambda1;->com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.f$1:Lcom/google/android/datatransport/runtime/TransportContext;

    iput-object p3, p0, Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler$$ExternalSyntheticLambda1;->com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.f$2:Lcom/google/android/datatransport/runtime/EventInternal;

    return-void
.end method


# virtual methods
.method public final com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.execute()Ljava/lang/Object;
    .registers 4

    iget-object v0, p0, Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler$$ExternalSyntheticLambda1;->com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.f$0:Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler;

    iget-object v1, p0, Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler$$ExternalSyntheticLambda1;->com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.f$1:Lcom/google/android/datatransport/runtime/TransportContext;

    iget-object v2, p0, Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler$$ExternalSyntheticLambda1;->com.google.android.datatransport.runtime.scheduling.DefaultScheduler$$InternalSyntheticLambda$2$7876631007fc8fb6b785707224cd9cac60856136e5c63650222501c2e428acf4$0.f$2:Lcom/google/android/datatransport/runtime/EventInternal;

    invoke-static {v0, v1, v2}, Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler;->$r8$lambda$gan_DuQtUIPPXez98St01P-VZPQ(Lcom/google/android/datatransport/runtime/scheduling/DefaultScheduler;Lcom/google/android/datatransport/runtime/TransportContext;Lcom/google/android/datatransport/runtime/EventInternal;)Ljava/lang/Object;

    move-result-object v0

    return-object v0
.end method

Or

.class public final synthetic Lcom/google/android/exoplayer2/audio/AudioListener$-CC;
.super Ljava/lang/Object;
.source "SourceFile"


# direct methods
.method public static a(Lcom/google/android/exoplayer2/audio/AudioListener;Lcom/google/android/exoplayer2/audio/AudioAttributes;)V
    .registers 2

    return-void
.end method

.method public static b(Lcom/google/android/exoplayer2/audio/AudioListener;I)V
    .registers 2

    return-void
.end method

Or

.class public final synthetic Lcom/company/di/DaggerAccountComponent$Builder-IA;
.super Ljava/lang/Object;
.source "SourceFile"

It's challenging to create a demo project with the same issue. From the commit I provided, would you please help to advise:

Any things that could help us mitigate the situation
If it's a project-specific issue. What should be the best approach to investigate this kind of problem?

ps: Currently, we force the project to use R8 3.0.x to avoid the case, but for some reason, we soon have to use the new R8 version.