Avoid new SSA var for ASSIGN_OBJ_REF without RC inference #13233
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Previously, this variable was necessary because of auto-vivification on UNDEF/NULL/false. It's now only used for RC inference. However, auto-vivification has been removed. This implicitly solves an inference problem for $obj->bar &= $obj; where we get a new variable for both literal references to $obj, with the first one getting the RCn flag, and the second one getting the MAY_BE_REFERENCE flag. Thus, the first variable will be missing the reference type, causing a false-positive type inference warning. If we want to verify RC inference at some point we'll need a better solution.
iluuu1994
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dstogov
approved these changes
Jan 23, 2024
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Previously, this variable was necessary because of auto-vivification on UNDEF/NULL/false. It's now only used for RC inference, as auto-vivification has been removed.
This implicitly solves an inference problem for $obj->bar &= $obj; where we get a new variable for both literal references to $obj, with the first one getting the RCn flag, and the second one getting the MAY_BE_REFERENCE flag. Thus, the first variable will be missing the reference type, causing a false-positive type inference warning.
If we want to verify RC inference at some point we'll need a better solution.
For reference: https://github.com/php/php-src/actions/runs/7619720239/job/20753304348