Fix GH-18847: set EX(opline) when the tracing JIT enters a call frame#22542
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iliaal wants to merge 1 commit into
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Fix GH-18847: set EX(opline) when the tracing JIT enters a call frame#22542iliaal wants to merge 1 commit into
iliaal wants to merge 1 commit into
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The tracing JIT enters a callee frame without writing EX(opline) to memory; it keeps the opline in the IP register and writes it back lazily. When a fatal error is raised before that first store, such as an out-of-memory while the callee's first opcode pushes its own call frame, zend_fetch_debug_backtrace() dereferences the NULL EX(opline). Materialize it at entry, as the observer path already did behind ZEND_OBSERVER_ENABLED. Fixes phpGH-18847
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Under the tracing JIT, entering a callee frame doesn't materialize EX(opline) in memory (it stays virtual in the IP register), so a fatal error raised at the frame's first opcode, e.g. an OOM while that opcode pushes its own call frame, makes zend_fetch_debug_backtrace() dereference a NULL opline. The store already existed on the observer path but was gated behind ZEND_OBSERVER_ENABLED; this drops the gate so it also runs with observers off. GH-18899 fixed the function-JIT undefined-variable variant of the same missing-opline class; this is the tracing-JIT call-entry sibling.
This adds one EX(opline) store per JIT call-frame entry (the store observer builds already emit), so flagging in case you'd prefer to narrow it. Fixes #18847