ERANGE strikes again: RFH

[j6t]

I have to build with SNPRINTF_RETURNS_BOGUS. We know already that compat/snprintf overwrites errno with ERANGE in the case where a too small buffer is passed to the function.

I observe failures such as this one in t0410-partial-clone.sh:

++ git -C repo fsck
Checking object directories: 100% (256/256), done.
Checking objects: 100% (1/1), done.
fatal: failed to read object 3836707...snip...6591523: Result too large

The messages is from read_object_file_extended() in sha1-file.c.
It looks like we call into strbuf after a lower-level error return,
but before the error is checked. Does someone know where this
could happen?

The reason I'm asking is that today's tool chain is sufficiently broken for me
on Windows that I can't use the debugger. A hint where to start debugging
with fprintf would be helpful.

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[dscho]

/allow

[gitgitgadget]

User j6t is now allowed to use GitGitGadget.

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[j6t]

I retract this patch for now. I have asked the mailing list to clarify whether restoration of errno like I do in this patch is actually necessary, or whether the caller that depends on that errno remains unmodified is bogus.