Fix GH-22490: NULL deref for a pipe on the lhs of ??=#22494
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lgtm, you might need a more refined commit title though
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Renamed for clarity. |
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zend_compile_var_inner did not route ZEND_AST_PIPE through zend_compile_memoized_expr, so a pipe on the left-hand side of ??= was recompiled during the FETCH pass. zend_compile_pipe synthesizes a fresh call node on each pass, so the memoized-result lookup keyed by that node returned NULL and was dereferenced. Memoize the pipe like the other call kinds zend_is_call() already recognizes. Fixes phpGH-22490
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Done, retitled the PR and commit to |
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A pipe expression on the left-hand side of
??=, e.g.(1 |> f(...))->g ??= 2, crashes the compiler with a NULL pointer dereference inzend_compile_memoized_expr. The coalesce-assign LHS is compiled twice and call results are memoized by AST-node pointer, butzend_compile_pipedesugars the pipe into a freshly allocated call node on each pass, so the fetch pass looks up a pointer the compile pass never stored. Memoizing the whole pipe under its stable original node, consistent withzend_is_call(), makes the pipe compile once and the fetch pass reuse the result.Fixes #22490