Don't emit != 0 when a C comparison or logical operator is returned as bool - #823
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…s bool In C, relational and logical operators yield `int`, so returning one from a `_Bool` function inserts an `IntegralToBoolean` cast. The equivalent C# operators already yield `bool`, making the `!= 0` coercion both redundant and non-compiling. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
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…teger The inverse of the != 0 case: in C, relational and logical operators yield int, so their result can be stored in or returned as an integer without a cast. The equivalent C# operators yield bool, which has no implicit conversion to an integer, so a ? 1 : 0 coercion must be inserted where such a value is returned from or assigned to an integer. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
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A C &&/|| yields int and promotes a _Bool operand to int, which the generator rendered as a ? 1 : 0 coercion. Since C#'s logical operators take bool operands directly, this produced invalid, mis-precedenced output like (a) ? 1 : 0 && (b) ? 1 : 0; emit the underlying bool instead. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>
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Fixes #820.
In C, relational (
< > <= >= == !=) and logical (&& ||) operators yieldint, so returning one from a_Boolfunction inserts anImplicitCastExpr<IntegralToBoolean>. The generator emitted(<expr>) != 0for that cast, but the equivalent C# operators already yieldbool, so the!= 0is both redundant and non-compiling (bool != int). C++ never hits this because<etc. already yieldbool(no cast inserted).The
CX_CK_IntegralToBooleanhandling now omits the!= 0whenever the operand is already a C#-boolean-valued expression -- a comparison, a logical&&/||, or a!-- and otherwise keeps the existing!= 0coercion (e.g.return someInt;). Bitwise&/|are intentionally left untouched, since(x & mask) != 0is genuinely int-to-bool.Regression test added as
CTest.BooleanReturnFromComparisonTestcovering the comparison, logical, and plain-integer cases.Not addressed here: the operands of a logical
&&/||with non-booloperands (e.g.int a, b; return a && b;) still emit invalida && b-- that is a separate, pre-existing issue and out of scope for this fix.