IssueTracker

open attachment link with viewing granted: https://drive.google.com/file/d/1935AH5-9WhLml8OQ9OWkQKJyZfyHtdgY/view?usp=sharing

Root cause is:

 Caused by: java.lang.VerifyError: Verifier rejected class com.google.android.material.appbar.AppBarLayout$Behavior: boolean com.google.android.material.appbar.AppBarLayout$Behavior.x(androidx.coordinatorlayout.widget.CoordinatorLayout, android.view.View, android.view.View, android.view.View, int, int) failed to verify: boolean com.google.android.material.appbar.AppBarLayout$Behavior.x(androidx.coordinatorlayout.widget.CoordinatorLayout, android.view.View, android.view.View, android.view.View, int, int): [0x2] 'this' argument 'Reference: com.google.android.material.appbar.AppBarLayout$Behavior' not instance of 'Precise Reference: de.wemode.bugdemo.CustomAppBarLayoutBehavior' (declaration of 'com.google.android.material.appbar.AppBarLayout$Behavior' appears in base.apk)

Using the attached project I was able to reproduce by running the app on emulator API 29. I've also attached the APK.

Here is the method that is causing the issue:

.method public bridge synthetic x(Landroidx/coordinatorlayout/widget/CoordinatorLayout;Landroid/view/View;Landroid/view/View;Landroid/view/View;II)Z
    .registers 7

    check-cast p2, Lcom/google/android/material/appbar/AppBarLayout;

    invoke-virtual/range {p0 .. p6}, Lcom/google/android/material/appbar/AppBarLayout$BaseBehavior;->N(Landroidx/coordinatorlayout/widget/CoordinatorLayout;Lcom/google/android/material/appbar/AppBarLayout;Landroid/view/View;Landroid/view/View;II)Z

    move-result p1

    return p1
.end method

Søren, can you please take a look?

This is an R8 bug introduced between 2.1.25-dev and 2.1.26-dev, more precisely by Generalize bridge hoisting.

git bisect start
# good: [5f086a0fb239f988c424b6e07bd6c97382616546] Deprecate TestBase.runtimeJar(Backend)
git bisect good 5f086a0fb239f988c424b6e07bd6c97382616546
# bad: [4732fa63e34129422d08843061e8597b19c691cd] Do not rewrite methods in the parser when doing resource shrinking
git bisect bad 4732fa63e34129422d08843061e8597b19c691cd
# good: [21953bac72b3831219fcffc2f1f5a764141b96d9] Remove unneeded assert bailout.
git bisect good 21953bac72b3831219fcffc2f1f5a764141b96d9
# good: [c9cf68284ff1bbcf49103edd3bfbba8551f7ca24] Harden assertion configuration analysis to allow input stack maps
git bisect good c9cf68284ff1bbcf49103edd3bfbba8551f7ca24
# bad: [53357603a80007f858d798e933921a43c6a1735f] Add support for flexible upper bound in kotlin metadata
git bisect bad 53357603a80007f858d798e933921a43c6a1735f
# bad: [603a4eb454ce107882bc9619c8b04f90ca9f8df0] Account for appInfo being null in AssemblyWriter
git bisect bad 603a4eb454ce107882bc9619c8b04f90ca9f8df0
# bad: [fd7372a8defbac071f3e960892d16f936100b036] Process kotlin.Metadata if the annotation will be output
git bisect bad fd7372a8defbac071f3e960892d16f936100b036
# bad: [15ead9f91812e5e564f68822cd972d0ac025dc24] Generalize bridge hoisting
git bisect bad 15ead9f91812e5e564f68822cd972d0ac025dc24
# first bad commit: [15ead9f91812e5e564f68822cd972d0ac025dc24] Generalize bridge hoisting

I have found the issue, and will send out a CL soon. It is caused by the bridge hoisting only rewriting invokes with 5 arguments or less (invoke-virtual and not innvoke-virtual/range) in hoisted bridges.

For the sample a valid workaround it this keep rule:

-keep class de.wemode.bugdemo.CustomAppBarLayoutBehavior {
  onStartNestedScroll(...);
}