Fix #633: [Bug] Stack-overflow due to infinite recursion in user-defined operator (string interpolation)#700
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lefticus merged 4 commits intoMay 2, 2026
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…ck overflow Recursive user-defined operators (e.g. a `string::/=` whose body calls itself through string interpolation) drove the AST evaluator into unbounded native recursion and crashed the host process with SIGSEGV. The dispatcher now refuses to enter a new function frame once `Stack_Holder::call_depth` reaches `chaiscript::max_call_depth` (default 256, overridable via the `CHAISCRIPT_MAX_CALL_DEPTH` macro) and throws the new `chaiscript::exception::stack_overflow_error` instead, letting both ChaiScript-level `try`/`catch` and C++ hosts recover from runaway recursion. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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@leftibot you have a failure on Windows, investigate. |
Windows MSVC Debug builds crashed unit.recursion_depth_protection.chai with SEGFAULT before the depth check could fire. Windows defaults to a 1 MiB thread stack and Debug builds emit much larger per-frame native stack usage (no inlining, /RTC, buffer security checks), so 256 nested ChaiScript calls overflow the native stack long before the dispatcher reaches max_call_depth. Linux/macOS and MSVC Release pass at 256. Pick a tighter default (32) only for the MSVC + _DEBUG configuration that needs it, leaving every other build at the original 256, and shrink the count_down recursion in the regression test so the bounded path stays well below every platform's default. Requested by @lefticus in PR ChaiScript#700 review. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Addressed review feedback from @lefticus. New commits: |
Switch CHAISCRIPT_DEBUG from a true/false definition to 1/0 so it can be used in preprocessor #if expressions, then reuse it for the MSVC Debug guard around CHAISCRIPT_MAX_CALL_DEPTH instead of testing the compiler-private _DEBUG macro directly. The C++ debug_build constant keeps its bool value through implicit conversion. Requested by @lefticus in PR ChaiScript#700 review. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Addressed review feedback from @lefticus. New commits: |
…yping C++ preserves the true/false keywords in #if directives ([cpp.cond]), so the MSVC Debug guard around CHAISCRIPT_MAX_CALL_DEPTH still works without weakening the macro to integer 1/0. Requested by @lefticus in PR ChaiScript#700 review. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Addressed review feedback from @lefticus. New commits: |
lefticus
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May 2, 2026
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Automated fix by @leftibot.
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Closes #633
Triggered by @lefticus.