Cast rhs to LHSTYPE in JRE_HANDLE_OVERFLOW_COMPOUND_ASSIGN. - #2817
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Cast rhs to LHSTYPE in JRE_HANDLE_OVERFLOW_COMPOUND_ASSIGN.#2817copybara-service[bot] wants to merge 1 commit into
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The `JRE_HANDLE_OVERFLOW_COMPOUND_ASSIGN` macro generates helper functions for compound assignment operators (e.g., `+=`, `-=`, `*=`) that handle overflow. When `LHSTYPE` (e.g., `jint`) is smaller than `RHSTYPE` (e.g., `jlong`), calling `Jre##LHSTYPENAME##NAME` (which expects `LHSTYPE` arguments) with `rhs` (which is `RHSTYPE`) triggers an implicit conversion warning/error (`-Wshorten-64-to-32`). This fix explicitly casts `rhs` to `LHSTYPE` before passing it to the overflow helper function. This is semantically equivalent to Java's compound assignment behavior for +, -, and *, where the result is eventually cast back to the LHS type, and modulo arithmetic ensures the bit pattern is correct even if we cast the RHS beforehand. PiperOrigin-RevId: 952958170
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Cast rhs to LHSTYPE in JRE_HANDLE_OVERFLOW_COMPOUND_ASSIGN.
The
JRE_HANDLE_OVERFLOW_COMPOUND_ASSIGNmacro generates helper functions for compound assignment operators (e.g.,+=,-=,*=) that handle overflow.When
LHSTYPE(e.g.,jint) is smaller thanRHSTYPE(e.g.,jlong), callingJre##LHSTYPENAME##NAME(which expectsLHSTYPEarguments) withrhs(which isRHSTYPE) triggers an implicit conversion warning/error (-Wshorten-64-to-32).This fix explicitly casts
rhstoLHSTYPEbefore passing it to the overflow helper function. This is semantically equivalent to Java's compound assignment behavior for +, -, and *, where the result is eventually cast back to the LHS type, and modulo arithmetic ensures the bit pattern is correct even if we cast the RHS beforehand.