chore: abort build on panic

nix/buildLeanPackage.nix

@@ -136,6 +136,7 @@ with builtins; let
   buildMod = mod: deps: mkBareDerivation rec {
     name = "${mod}";
     LEAN_PATH = depRoot mod deps;
+    LEAN_ABORT_ON_PANIC = "1";
     relpath = modToPath mod;
     buildInputs = [ lean ];
     leanPath = relpath + ".lean";

src/stdlib.make.in

@@ -3,6 +3,7 @@ SHELL := /usr/bin/env bash -euo pipefail
 # any absolute path to the stdlib breaks the Makefile
 export LEAN_PATH=
 export LEAN_CC=${CMAKE_C_COMPILER_LAUNCHER} ${CMAKE_C_COMPILER}
+export LEAN_ABORT_ON_PANIC=1
 
 # LEAN_OPTS: don't use native code (except for primitives) since it is from the previous stage
 # MORE_DEPS: rebuild the stdlib whenever the compiler has changed