SIGSEGV in dynamic when key not in context about humbleui

[tonsky]

Thanks @Folcon, good idea

[tonsky]

@Folcon what do you mean? Like this

(ui/dynamic ctx [key (:unknown ctx)]

This works fine for me

[Folcon]

Ok looking at my crashdumps, I think I've made a mistake, the issue occurs, but the cause is not ui/dynamic misbehaving specifically.

The issue is components which are created which when I use them in another context and they're missing expected keys causes a jvm crash, as libskija is less forgiving.

For example:

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00000001506f15f9, pid=51839, tid=775
#
# JRE version: OpenJDK Runtime Environment Homebrew (17.0.2) (build 17.0.2+0)
# Java VM: OpenJDK 64-Bit Server VM Homebrew (17.0.2+0, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, bsd-amd64)
# Problematic frame:
# C  [libskija_x64.dylib+0x2f15f9]  SkPaint::nothingToDraw() const+0x9
#
# No core dump will be written. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again

~~~ ELIDED ~~~

---------------  T H R E A D  ---------------

Current thread (0x00007fe41200bc00):  JavaThread "main" [_thread_in_native, id=775, stack(0x00007ffee2515000,0x00007ffee6514000)]

Stack: [0x00007ffee2515000,0x00007ffee6514000],  sp=0x00007ffee65099a0,  free space=65490k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
C  [libskija_x64.dylib+0x2f15f9]  SkPaint::nothingToDraw() const+0x9
C  [libskija_x64.dylib+0x264f57]  SkCanvas::internalQuickReject(SkRect const&, SkPaint const&, SkMatrix const*)+0x47
C  [libskija_x64.dylib+0x266c0f]  SkCanvas::onDrawRect(SkRect const&, SkPaint const&)+0x1f
C  [libskija_x64.dylib+0x265605]  SkCanvas::drawRect(SkRect const&, SkPaint const&)+0xb5
C  [libskija_x64.dylib+0x7d9b]  Java_io_github_humbleui_skija_Canvas__1nDrawRect+0x2b
J 7455  io.github.humbleui.skija.Canvas._nDrawRect(JFFFFJ)V (0 bytes) @ 0x00000001229120a9 [0x0000000122911fa0+0x0000000000000109]
j  io.github.humbleui.skija.Canvas.drawRect(Lio/github/humbleui/types/Rect;Lio/github/humbleui/skija/Paint;)Lio/github/humbleui/skija/Canvas;+67

The problem may not be solvable, but yea, getting a better idea of what's wrong while developing and preferably not having crashes would be good.

If that's out of scope, sorry, feel free to close =)...

[tonsky]

Actually... Try enabling asserts? -ea is JVM option. It should check for nulls in Skija and throw instead of dying silently

[Folcon]

So good news is that it's stopped crashing, bad news if the assert exception propagates through it seems to lockup everything.

The repl is active, but each time I try to reload a good state, it keeps throwing the same exception.

Hmm, I'll see if I can catch the exception better.

[tonsky]

Should’ve been fixed in acead0c

[Folcon]

@tonsky, you might want to catch Throwable instead of Exception as asserts cause similar "locking up" behaviour?

Or is that too much?