native tracer: fix unwinding eh_frame entries ending in a call instuction#1382
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…ction It seems compilers can fairly often generate .eh_frame entries ending in a 'call' instruction. The unwinder would match the immediate next eh_frame in this case as it was not taking into account unwinding state. Since we now have 'return_address' state available, use that to adjust the lookup address to be able to match the CALL instruction at the end of FDE. The problem this introduces is unwinding signal frame handlers. Those are injected to the stack, and the FDE typically does not cover the preceding byte (which is not a CALL instruction or even part of the FDE). To keep things working, adjust the signal frame command address by -1 so that unwindier will find the signal handler FDE.
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christos68k
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florianl
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This was referenced May 15, 2026
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It seems compilers can fairly often generate .eh_frame entries ending in a 'call' instruction. The unwinder would match the immediate next eh_frame in this case as it was not taking into account unwinding state. Since we now have 'return_address' state available, use that to adjust the lookup address to be able to match the CALL instruction at the end of FDE.
The problem this introduces is unwinding signal frame handlers. Those are injected to the stack, and the FDE typically does not cover the preceding byte (which is not a CALL instruction or even part of the FDE). To keep things working, adjust the signal frame command address by -1 so that unwindier will find the signal handler FDE.