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…keys
A call nested in an expression can be materialized into a pre-statement
temporary. Two constructs emitted those temporaries before work that PHP
performs first, so side effects (output, mutations, exceptions) happened in
the wrong order.
echo: `echo a, b, c` prints each operand before evaluating the next one.
parseEcho() emits one php::echo() per operand, but every operand's hoisted
lines were emitted before the first php::echo():
function f(string $s): string { echo "[f:$s]"; return $s; }
echo "A", var_export(f("1"), true), "\n";
// PHP: A[f:1]'1'
// compiled: [f:1]A'1'
echo "E-", var_export(boom(), true); // boom() throws
// PHP prints "E-" before the exception; the binary printed nothing.
The pre- and post-statement lines produced while parsing an operand are now
emitted around that operand's own php::echo().
Array literals: PHP evaluates a key before its value. parseArrayMixed()
parsed the value first, so a value that is a call was materialized before
an inline key expression:
[f("k1") => strtoupper(f("v1")), f("k2") => f("v2")]
// PHP: [k1][v1][k2][v2]
// compiled: [v1][k1][v2][k2]
A side-effecting key is now materialized before its value is parsed.
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Fixes #143
A call nested in an expression can be materialized into a pre-statement temporary. Two constructs emitted those temporaries before work PHP performs first.
The change
echo(CompilerBase::parseEcho()): it already emits onephp::echo()per operand, but every operand's hoisted lines landed before the firstphp::echo(). The pre- and post-statement lines produced while parsing an operand are now emitted around that operand's ownphp::echo(), so each operand is evaluated after the previous one has been printed — including when it throws.ArrayExpressionTrait::parseArrayMixed()): the value was parsed before the key, so a value that is a call was materialized ahead of an inline key expression. A side-effecting key (shouldMaterializeOrderedOperand()) is now materialized withparseOrderedOperand()before the value is parsed. Literal keys are untouched (they also never reach this path with side effects inparseArray()).Verified on a binary
PHP 8.4.26 ZTS with embed, GCC 11, Linux x64.
?:,sprintf) compared with PHPtests/compiler/basic/echo-operand-order.phpt[f:1]A'1')tests/compiler/array/array-key-evaluation-order.phpt[v1][k1][v2][k2])tests/compiler(full)Found with a differential fuzzer (same session as #137 and #140).