Re: [PATCH] autoconf: Add tests for memmem, strtoumax and mkdtemp functions

Shawn O. Pearce wrote:

Jakub Narebski [off-list ref] wrote:

quoted

By the way, do you have idea how to test for the following
in configure.ac:

* Define NO_PREAD if you have a problem with pread() system call (e.g.
  cygwin.dll before v1.5.22).

  - what is the problem? how to detect it?

This also appears to be broken on HP-UX (e.g. we need to set
NO_PREAD there).  Thiago on IRC talked about this the other day
when he was trying to build git on a bunch of different systems.

Unfortunately this may just need to be an OS based test.  The code
compiles just fine but when index-pack tries to use pread to walk
back through the deltas and generate their SHA-1s it barfs without
an error code.  I suspect the failure is pread claiming it put the
data into the user buffer but not actually doing so, which causes
zlib's inflate() to then see data corruption.

Can you write a short program which demonstrates this error (either
fails with some error code, or produces wrong output)? That would be
enough for configure.ac (see for example NO_C99_FORMAT in configure.ac)

Unless this is Schroedinger bug...

-- 
Jakub Narebski
Poland