Fix #894: reset mathcnt when a call statement closes an if-block#906
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…lock Two consecutive `if <cond with && or ||> then <function/event call> end` blocks compiled incorrectly: the first block's trailing OP_AND/OP_OR was relocated into the second block, so both conditions evaluated wrong and both bodies ran regardless of the condition. The corruption is present in the parser output (before bc_assign_slots), so it is not a slot-assignment bug. Root cause: the assignment-statement path resets the temporary slot counter (mathcnt = 0) but the call/ expression-statement path does not. When a call statement closes an if-block, the leftover mathcnt makes the next sibling if-condition's first operand get a slot index != 1, so bc_parse_math_order's backward search for the start of the current expression overshoots past the previous block's call body and JMP into that block's first OP_GETVAL, pulling its trailing logical operator into the new block. Reset mathcnt in the statement terminator's TEND branch, i.e. only when a call/expression statement is the last in its block. Doing it after every statement would change slot reuse for multi-statement bodies; scoping it to block close keeps previously-correct bytecode byte-identical. Validated against the upstream CurlyMoo/rules unit-test suite (all 526 tests pass, no regressions) and a standalone bytecode harness covering the &&/||, multi-statement-body, nested-if and value-returning-call cases. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Two consecutive
if <cond with && or ||> then <function/event call> endblocks compiled incorrectly: the first block's trailing OP_AND/OP_OR was relocated into the second block, so both conditions evaluated wrong and both bodies ran regardless of the condition.The corruption is present in the parser output (before bc_assign_slots), so it is not a slot-assignment bug. Root cause: the assignment-statement path resets the temporary slot counter (mathcnt = 0) but the call/ expression-statement path does not. When a call statement closes an if-block, the leftover mathcnt makes the next sibling if-condition's first operand get a slot index != 1, so bc_parse_math_order's backward search for the start of the current expression overshoots past the previous block's call body and JMP into that block's first OP_GETVAL, pulling its trailing logical operator into the new block.
Reset mathcnt in the statement terminator's TEND branch, i.e. only when a call/expression statement is the last in its block. Doing it after every statement would change slot reuse for multi-statement bodies; scoping it to block close keeps previously-correct bytecode byte-identical.
Validated against the upstream CurlyMoo/rules unit-test suite (all 526 tests pass, no regressions) and a standalone bytecode harness covering the &&/||, multi-statement-body, nested-if and value-returning-call cases.