tree 521ea23934f8280e71ad581d5028d9f045424c9e
parent 9aaec95e82117c1cb0f9624264c3618fc380cecb
author Mark Adler <madler@alumni.caltech.edu> 1474526150 -0700
committer Mark Adler <madler@alumni.caltech.edu> 1474526150 -0700

Remove offset pointer optimization in inftrees.c.

inftrees.c was subtracting an offset from a pointer to an array,
in order to provide a pointer that allowed indexing starting at
the offset. This is not compliant with the C standard, for which
the behavior of a pointer decremented before its allocated memory
is undefined. Per the recommendation of a security audit of the
zlib code by Trail of Bits and TrustInSoft, in support of the
Mozilla Foundation, this tiny optimization was removed, in order
to avoid the possibility of undefined behavior.