7a58da1181
eval_expr creates auxiliary definitions in the VM. These auxiliary definitions are gone after the VM finishes. We store vm_obj's in the attribute_manager. Before this commit, Lean was crashing in the following scenario: 1- A new caching_user_attribute is defined, and the user data structure contains closures. 2- The closures are created using eval_expr. 3- When reusing the cached values, the system crashes when trying to apply a closure created using eval_expr. The closure points to an auxiliary definition that has already been deleted. The new test exposes the problem. This is not a hypothetical scenario, the new test is based on the Lean - Mathematica integration being developed by @rlewis1988. The fix consists in making sure we do not cache anything if the VM environment has been updated by eval_expr. I believe this is acceptable behavior. eval_expr is a very low level tactic, and I don't see a good motivation for invoking it when constructing the cache. BTW, the test can be relaxed if the vm_attr does not contain closures. However, it doesn't seem to pay off. Another potential fix would be to propagate the definitions created by eval_expr to the main environment. However, I think this is not acceptable. We will be flooding the main environment with useless temporary definitions created by `eval_expr`. This commit also stores the environment at caching time, and make sure the cache is only reused if the current environment is a descendant of the the one at caching time. This is fixing a different potential bug. |
||
|---|---|---|
| .. | ||
| api | ||
| checker | ||
| cmake | ||
| emacs | ||
| frontends | ||
| init | ||
| kernel | ||
| library | ||
| shared | ||
| shell | ||
| tests | ||
| util | ||
| vim | ||
| CMakeLists.txt | ||
| CTestConfig.cmake | ||
| CTestCustom.cmake.in | ||
| Doxyfile | ||
| githash.h.in | ||
| memcheck.supp | ||
| version.h.in | ||