Steps to reproduce:

1. Download the attached project and open TestScene01 (Assets > Scenes)
2. Navigate to the Lighting Settings window and make sure that Progressive GPU lightmapper is selected
3. Press Generate Lighting
4. Observe a crash

Notes:

- Reproduces on 2019.1.0a3 (trunk), 2019.1.0a1, 2018.3.0b2, 2018.3.0b1
- Reproduces on public and katana builds
- Does not reproduce on debug builds
- Reproduces only when light probes are present within a scene
- Reproduces when baking with AMD R9 Nano Fury GPU; does not reproduce with GTX1080

Stack trace:

========== OUTPUTTING STACK TRACE ==================

RtlLookupFunctionEntry returned NULL function. Aborting stack walk.
0x00007FF90002CB12 (mono-2.0-bdwgc) [c:\buildslave\mono\build\mono\mini\exceptions-amd64.c:540] get_throw_trampoline
[PathTracer] Composited not yet converged lightmap; index: 0, lightmap composite hash: f590a81aa6e2fe9d8ee028796a56fd79, lightmap hash: 38f7fb27515fdeac42a0ed5e3a2aa3d9, render pass hash: 5d3f0d0a67c80c228f6c935ecaa8ded0, took 0.468s -> Timestamps: [139.606 - 140.074].
[PathTracer] Lightmap render 0 for 38f7fb27515fdeac42a0ed5e3a2aa3d9 -> scheduledDirect: 0rpt, scheduledGI: 1rpt, fired: 157.71 krays in 0.00 secs (32.26 mrays/sec) -> Timestamps: [942237.912 - 942237.917], renderedOneFrame: true
[PathTracer - GPU] Finished CullLightmap -> took 0.002s -> Timestamps: [942237.394 - 942237.396]
[PathTracer - GPU] Finished CompositeLightmap -> took 0.005s -> Timestamps: [942237.931 - 942237.936]
[PathTracer] Lightmap render 1 for 38f7fb27515fdeac42a0ed5e3a2aa3d9 -> scheduledDirect: 0rpt, scheduledGI: 1rpt, fired: 157.69 krays in 0.00 secs (131.55 mrays/sec) -> Timestamps: [942237.937 - 942237.938], renderedOneFrame: true
[PathTracer - GPU] Lightmap convergence 38f7fb27515fdeac42a0ed5e3a2aa3d9 -> (min/max/avg) Direct (0/0/0), GI (0/1/0), convergedInView: false, converged: false, visible: 150024, occupied: 177710.
[PathTracer - GPU] Lightmap convergence 38f7fb27515fdeac42a0ed5e3a2aa3d9 -> (min/max/avg) Direct (0/0/0), GI (0/2/1), convergedInView: false, converged: false, visible: 150024, occupied: 177710.
[PathTracer] Issuing lightmap composite job for a not converged lightmap; index: 0, lightmapCompositeHash: 0e7f0eb31675ce97db515d151b9d3089, lightmapHash: 38f7fb27515fdeac42a0ed5e3a2aa3d9, renderPassHash: 5d27a2e24881b5ccbf4e23e1d35829c6, compositingHash: 81acf81de99ebee642c92c24e26811fe.
0x00007FF96D025F07 (KERNELBASE) SleepEx
<Missing stacktrace information>

========== END OF STACKTRACE ===========

A crash has been intercepted by the crash handler. For call stack and other details, see the latest crash report generated in:
* C:/Users/KRISTI~1/AppData/Local/Temp/Unity/Editor/Crashes
[PathTracer] Setting pending lightmap data, so that it's used for rendering; hash: 6b505c2cf16b8940e8544cac7b0efab5.
[PathTracer] lightmap hash: 38f7fb27515fdeac42a0ed5e3a2aa3d9, instanceID: -2048.
[PathTracer][LP] Runtime and context manager light probe state has stabilised on hash a1ea25dd1c36a455b6dea24a4cf3f91a.
[PathTracer][LP] Setting pending light probes data, so that it's used for rendering. Hash: d7ab52c3fc039c48fb1e31f7b16e12e7.
[PathTracer][LP] light probes hash: 88bbfb0ac77509350186677a948ce76c, render pass hash: 23f040b61df81bda25adefc5f5d1db9b.
[PathTracer] Issuing a render job for lightmap 38f7fb27515fdeac42a0ed5e3a2aa3d9, visible texels: 150024, Timestamps: [140.115].
[PathTracer] Issuing a convergence job for lightmap 38f7fb27515fdeac42a0ed5e3a2aa3d9.
Refresh: detecting if any assets need to be imported or removed ...