Fix for(;;) NullReferenceException in parser - #113
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…in FOR rules - Update 4 FOR grammar rules in CParser.jay to use reference type null checking (`$4 is ExpressionStatement es ? es.Expression : null`) - Make ForStatement.ContinueExpression nullable and skip condition emission when null (infinite loop until break) - Regenerate parser via prebuild.sh - Add tests for for(;;), for(i=0;;i++), for(i=0;i<10;), for(;i<5;i++) Agent-Logs-Url: https://github.com/praeclarum/CLanguage/sessions/4fd85394-830c-4edd-b5a1-71623366c29b Co-authored-by: praeclarum <323548+praeclarum@users.noreply.github.com>
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[WIP] Fix NullReferenceException in parser for infinite for loops
Fix for(;;) NullReferenceException in parser
Mar 31, 2026
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March 31, 2026 20:29
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Instead of $4 is ExpressionStatement es4a ? es4a.Expression : null etc I would prefer the simpler ($4 as ExpressionStatement)?.Expression. Unless that doesn't work for some reason...
Use ($4 as ExpressionStatement)?.Expression instead of pattern matching. Agent-Logs-Url: https://github.com/praeclarum/CLanguage/sessions/3f96ebb4-83a6-41af-bf99-d72fe14ad18f Co-authored-by: praeclarum <323548+praeclarum@users.noreply.github.com>
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Updated all 4 rules to use |
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Mar 31, 2026
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for(;;)and other for-loops with empty expressions crash withNullReferenceExceptionbecauseexpression_statement: ';'returnsnull, and the FOR grammar rules blindly cast toExpressionStatement.Changes
CParser.jay— All 4 FOR rules useaswith null-conditional operator instead of direct cast:ForStatement.cs—ContinueExpressionmade nullable;DoEmitskips the conditional branch when null (infinite loop untilbreak)CParser.cs— Regenerated viaprebuild.shfor(;;),for(i=0;;i++),for(i=0;i<10;),for(;i<5;i++)