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changeset 577:e49d24f4a9a5
Correct bug in the object file output code leading to stack corruption
It turns out leaving a pointer to a stack allocated temporary in a
persistent data structure is not conducive to correct program operation.
Undo the export check setup in the object file output sequence so a
pointer to stack allocated memory is not left hanging when the function
returns. This seems to correct at least one mysterious crash bug, and
possibly others.
Thanks to Boisy Pitre for reporting the crash bug that led to this
discovery, as well as a previous crash bug that likely has the same
root cause.
Additional thanks to Ciaran Anscomb whose debugger wielding wizardry
revealed the exact location of this particular bit of unbrilliance.
| author | William Astle <lost@l-w.ca> |
|---|---|
| date | Sat, 03 Aug 2024 14:30:06 -0600 |
| parents | 40edb7de3857 |
| children | ff5a5ce952f1 |
| files | lwasm/output.c |
| diffstat | 1 files changed, 4 insertions(+), 0 deletions(-) [+] |
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--- a/lwasm/output.c Fri Jul 12 23:02:57 2024 -0600 +++ b/lwasm/output.c Sat Aug 03 14:30:06 2024 -0600 @@ -1000,6 +1000,10 @@ buf[0] = (offset >> 8) & 0xff; buf[1] = offset & 0xff; writebytes(buf, 2, 1, of); + + // clean up after ourselves so other stuff doesn't explode + as -> cl = NULL; + as -> exportcheck = 0; } // flag end of incomplete references list