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…etic and unary minus
Native bool values reached raw C++ operators that treat them as the integers
0 and 1, which differs from PHP in three places:
- Relational comparison. PHP compares a bool with any other scalar as two
bools (false < true); the C++ operator compared numerically:
function le(bool $a, int $b): bool { return $a <= $b; }
le(false, -7); // PHP: true compiled: false
<, <=, > and >= now convert the non-bool scalar operand to bool. == and
<=> already used php::equals()/php::compare().
- Arithmetic. A bool operand of +, -, * or / was not treated as an int, so
the checked varint paths did not apply and `7 / false` divided by a raw
bool: a SIGFPE even with `use varint_types`, where PHP raises
DivisionByZeroError. Bool operands are now converted to int first. % is
unchanged: a non-int operand already takes php::fn::mod.
- Unary minus. -$bool stayed a bool (-true printed `true`, PHP gives -1). It
is now an int, and a non-numeric operand (e.g. a string) is lowered like
Zend does, as multiplication by -1, matching what unary plus already does.
The inferred types follow (bitwise/shift/arithmetic operators treat a bool
operand as int; -bool is int; minus of a non-numeric value is dynamic).
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Fixes #145
Native bool values reached raw C++ operators that treat them as the integers 0 and 1.
The change
BinaryOpTrait::parseBinaryOp()): when exactly one operand of<,<=,>or>=is a bool, the other int/float/string operand is converted to bool, as PHP compares them.==and<=>already go throughphp::equals()/php::compare()and are unchanged.+,-,*or/is converted to int first, so the existing int paths apply — in particular the checked varint division, which turns7 / falsefrom a SIGFPE intoDivisionByZeroError.%is left alone on purpose: a non-int operand already takesphp::fn::mod(converting it would move native-mode%onto the raw C++ operator). Native-mode/keeps the documented raw int division (see Native mode: a runtime zero divisor or PHP_INT_MIN % -1 kills the process (SIGFPE) #142).UnaryExpressionTrait::parseUnaryMinus()):-$boolis an int, and a non-numeric operand is lowered like Zend does, as multiplication by-1— the same approach unary plus already uses (fix(compiler): apply unary plus numeric conversion #132).-boolis int, and minus of a non-numeric value is dynamic.Verified on a binary
PHP 8.4.26 ZTS with embed, GCC 11, Linux x64. 25 cases (bool vs int/float/string for each relational operator in both orders,
bool + int,bool * bool,float - bool,int / bool,int % bool,-true,-false,-"5",-"1.5",-"abc",$x = -true, division/modulo byfalse):use varint_types7 / false7 / false, the documented native int division (unchanged, #142)operator/bool-operands-native.phptandbool-operands-varint.phpttests/compiler(full)Found with a differential fuzzer.