lets try to capture from stack traces

.github/workflows/test_rust.yml

@@ -58,7 +58,7 @@ jobs:
         if: runner.os == 'Linux'
         run: |
           sudo apt-get update
-          sudo apt install -y libasound2-dev libxcb-shape0-dev libxcb-xfixes0-dev libgtk-3-dev mesa-vulkan-drivers libpango1.0-dev libudev-dev
+          sudo apt install -y libasound2-dev gdb libxcb-shape0-dev libxcb-xfixes0-dev libgtk-3-dev mesa-vulkan-drivers libpango1.0-dev libudev-dev
 
       # Needed after: https://github.com/rust-lang/rust/pull/124129
       # See also: https://github.com/dtolnay/linkme/issues/94
@@ -81,7 +81,10 @@ jobs:
 
       - name: Run tests with image tests
         if: runner.os != 'macOS'
-        run: cargo nextest run --profile ci --cargo-profile ci --workspace --locked --no-fail-fast -j 4 --features imgtests,lzma,jpegxr
+        run: |
+          set +e
+          cargo nextest run --profile ci --cargo-profile ci --workspace --locked -j 4 --features imgtests,lzma,jpegxr render
+          cat $(find . -name gdb.bt)
         env:
           # This is to counteract the disabling by rust-cache.
           # See: https://github.com/Swatinem/rust-cache/issues/43
@@ -92,6 +95,7 @@ jobs:
           # Workaround for: https://github.com/nextest-rs/nextest/issues/1493
           # See also: https://github.com/rust-lang/rustup/issues/3825
           RUSTUP_WINDOWS_PATH_ADD_BIN: '1'
+          CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_RUNNER: "./bt.sh"
           XDG_RUNTIME_DIR: '' # dummy value, just to silence warnings about it missing
 
       - name: Run tests without image tests

bt.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+# sauce : https://stackoverflow.com/a/63901492
+# kredit: https://blog.cryptomilk.org/2010/12/23/gdb-backtrace-to-file/
+
+ex=(
+    -ex "run"
+    -ex "set logging overwrite off"
+    -ex "set logging file gdb.bt"
+    -ex "set logging on"
+    -ex "set pagination off"
+    -ex "handle SIG33 pass nostop noprint"
+    -ex "echo backtrace:\n"
+    -ex "backtrace full"
+    -ex "echo \n\nregisters:\n"
+    -ex "info registers"
+    -ex "echo \n\ncurrent instructions:\n"
+    -ex "x/16i \$pc"
+    -ex "echo \n\nthreads backtrace:\n"
+    -ex "thread apply all backtrace"
+    -ex "set logging off"
+    -ex "quit"
+)
+echo 0 | gdb -batch-silent "${ex[@]}" --args "$@"
+