-#C faults on the first cache entry it names - #1412
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url_savename() opened by loading sback->lnk into a local that nothing reads until a branch the -#C lister never enters. That lister has no backing and passes NULL, so listing a legacy hts-cache/new.ndx faults on the first entry its pattern matches. Take the local where the block that uses it starts, and skip the type-probing request when there is no backing to issue it with. The unconditional load was also undefined behaviour on a NULL sback, which let the optimizer drop the later NULL tests as unreachable. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
The self-test's delayed= knob mirrors -%N, not -#N: case 'N' setting savename_delayed lives in htscoremain.c's '%' family, while '#' is the separate undocumented debug switch. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
xroche
enabled auto-merge (squash)
August 24, 2026 21:25
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url_savename()opened by loadingsback->lnkinto a local that nothing reads until a branch the-#Clister never enters. That lister has no backing and passes NULL, so listing a legacyhts-cache/new.ndxfaults on the first entry its pattern matches, before it prints anything. The local now comes from the block that uses it, and the type-probing request further down, the last thing on that path to touch the backing, is skipped when there is none.That second half is not belt and braces: reading
sback->lnkup front is undefined behaviour when it is NULL, so the compiler may delete any NULL test ofsbackthat follows, and at -O2 it does. A mutant carrying the load with the guard in place still crashed, in the guarded branch. The new test drivesurl_savename()with no backing through anosback=knob on-#test=savename, and reds on either mutant. End to end, a hand-built legacy ndx over a one-entry cache kills master at htsname.c:413 and lists cleanly once patched.Closes #1393