Fix GH-20319: Prevent ASSIGN_OP / ASSIGN_DIM_OP lvalue from being invalidated during assignment #20326
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−104
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…ssignment In ASSIGN_DIM_OP, side effects of coercion may release the array or make the dimension pointer invalid (by reallocating the array). Increasing the array's refcount around the binary op is enough to prevent both issues. In ASSIGN_OP, if the variable is a reference, side effects may release it. Again, increasing the refcount prevents this.
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In ASSIGN_DIM_OP, side effects of coercion may release the array or make the dimension pointer invalid (by reallocating the array). Increasing the array's refcount around the binary op is enough to prevent both issues.
In ASSIGN_OP, if the variable is a reference, side effects may release it. If the variable is a var-var slot, it may be invalidated if the symbol table is resized. In the former case, increase the refcount around the binary op. In the latter, turn the slot into a reference so we can apply the same fix.
Fixes: GH-20319
Related: GH-15938