feat: CI: capture core dumps

.github/workflows/ci.yml

@@ -157,6 +157,12 @@ jobs:
           # open nix-shell once for initial setup
           true
         if: matrix.os == 'ubuntu-latest'
+      - name: Set up core dumps
+        run: |
+          mkdir -p $PWD/coredumps
+          # store in current directory, for easy uploading together with binary
+          echo $PWD/coredumps/%e.%p.%t | sudo tee /proc/sys/kernel/core_pattern
+        if: matrix.os == 'ubuntu-latest'
       - name: Build
         run: |
           mkdir build
@@ -203,6 +209,7 @@ jobs:
       - name: Test
         run: |
           cd build/stage1
+          ulimit -c unlimited # coredumps
           # exclude nonreproducible test
           ctest -j4 --output-on-failure -E leanlaketest_git ${{ matrix.CTEST_OPTIONS }} < /dev/null
         if: ${{ !matrix.cross }}
@@ -233,6 +240,22 @@ jobs:
         if: matrix.name == 'Linux'
       - name: CCache stats
         run: ccache -s
+      - name: Show stacktrace for coredumps
+        if: ${{ failure() }} && matrix.os == 'ubuntu-latest'
+        run: |
+          for c in coredumps/*; do
+            progbin="$(file $c | sed "s/.*execfn: '\([^']*\)'.*/\1/")"
+            echo bt | $GDB/bin/gdb -q $progbin $c || true
+          done
+      - name: Upload coredumps
+        uses: actions/upload-artifact@v3
+        if: ${{ failure() }} && matrix.os == 'ubuntu-latest'
+        with:
+          name: coredumps-${{ matrix.name }}
+          path: |
+            ./coredumps
+            ./build/stage1/bin/lean
+            ./build/stage1/lib/lean/libleanshared.so
 
   release:
     if: startsWith(github.ref, 'refs/tags/')

shell.nix

@@ -21,6 +21,7 @@ in { pkgs ? flakePkgs.nixpkgs, pkgsDist ? pkgs }:
     GLIBC_DEV = pkgsDist.glibc.dev;
     GCC_LIB = pkgsDist.gcc.cc.lib;
     ZLIB = pkgsDist.zlib;
+    GDB = pkgsDist.gdb;
   });
   nix = flake.devShell.${builtins.currentSystem};
 }