Commit a9c4dc84f4

sin-ack <sin-ack@users.noreply.github.com>
2022-08-12 23:51:07
Sema: Revert sema.err to null if the Decl already has an error
Previously we would assign the error message to Sema and then never clear it even when destroying the error message, which caused memory corruption. Closes #12437
master
1 parent 40eac90
Changed files (1)
src
Sema.zig
src/Sema.zig
@@ -1906,8 +1906,6 @@ fn failWithOwnedErrorMsg(sema: *Sema, err_msg: *Module.ErrorMsg) CompileError {
     }
 
     const mod = sema.mod;
-    sema.err = err_msg;
-
     {
         errdefer err_msg.destroy(mod.gpa);
         if (err_msg.src_loc.lazy == .unneeded) {
@@ -1925,8 +1923,10 @@ fn failWithOwnedErrorMsg(sema: *Sema, err_msg: *Module.ErrorMsg) CompileError {
     const gop = mod.failed_decls.getOrPutAssumeCapacity(sema.owner_decl_index);
     if (gop.found_existing) {
         // If there are multiple errors for the same Decl, prefer the first one added.
+        sema.err = null;
         err_msg.destroy(mod.gpa);
     } else {
+        sema.err = err_msg;
         gop.value_ptr.* = err_msg;
     }
     return error.AnalysisFail;