https://issues.dlang.org/show_bug.cgi?id=22365
--- Comment #2 from [email protected] --- (In reply to RazvanN from comment #1) > The chances of this bug getting fixed without a minimal reproducible test > case are small. Maybe you can use DustMite [1] to reduce it? > > [1] > https://dlang.org/blog/2020/04/13/dustmite-the-general-purpose-data- > reduction-tool/ nope, unfortunately I wasn't able to reduce it yet, this is a complex library with tons of dependencies and it is happily reduces it down to 'import ;'. I'll try again later, meanwhile I traced down the issue and ready to submit possible fix (I hope that's a real fix and not just symptoms mending) PR after I double check everything. Here is an overview ----------------------------------------- dmd issue 22365 calls: [1] semantic3.d:1369 Semantic3Visitor.visit(CtorDeclaration) at 1446 TryCatchStatemt generation [2] semantic3.d:208 Semantic3Visitor.visit(FuncDeclaration) at 595 statementSemantic(funcdecl.fbody, sc2) call [3] statementsem.d:148 statementSemantic(Statement, Scope*) at 145 StatementSemanticVisitor.accept() [4] statement.d:1580 TryCatchStatemt.accept (just in case) [5] statementsem.d:3936 StatementSemanticVisitor.visit(TryCatchStatemt) at 3957 semanticScope() <--- here, returns wrong scope [6] statementsem.d:4486 semanticScope(Statement, Scope*, Statement, Statement, Statement) <--- push & pop the same scope? [7] statementsem.d:4473 semanticNoScope(Statement, Scope*) at 4468 statementSemantic() returns null which triggers assert above [8] statementsem.d:236 StatementSemanticVisitor.visit(CompoundStatent) at 257-264 flatten() and then statementSemantic() [9] statementsem.d:4631 flatten(Statement, Scope*) probably at 4720 if condition specifically look: [5] https://github.com/dlang/dmd/blob/96b959e27c690f5e3abf411f8032c60f4728c1c1/src/dmd/statementsem.d#L3936 [6] https://github.com/dlang/dmd/blob/96b959e27c690f5e3abf411f8032c60f4728c1c1/src/dmd/statementsem.d#L4497 so, at step 6 when using debbuger after semanticNoScope() restore s (null at this moment) back to original s (from function argument), now it works as expected > s = s.semanticNoScope(scd); // <- null > /* restore s */ > scd.pop(); > return s; tracing it further... [8] https://github.com/dlang/dmd/blob/96b959e27c690f5e3abf411f8032c60f4728c1c1/src/dmd/statementsem.d#L255 calling flatten() produces Statements[] array with single null element which is then returned as valid result here around line 420 > if (cs.statements.length == 1) > { > result = (*cs.statements)[0]; > return; > } [9] https://github.com/dlang/dmd/blob/96b959e27c690f5e3abf411f8032c60f4728c1c1/src/dmd/statementsem.d#L4726 debug condition doesn't get picked up and returns that Statements[] array with single null element afterwards > if (cs.condition.include(sc)) can be fixed with adding else if check for null and else return 0 here https://github.com/dlang/dmd/blob/96b959e27c690f5e3abf411f8032c60f4728c1c1/src/dmd/statementsem.d#L4737 this doesn't happens when adding debug else condition to original problem source, or replacing debug with version (all/none) or anything else, so there is a logic issue related to debug ConditionStatement somewhere --
