Log Message:
Changes 1.3.23:

Special Issues:
* Due to GCC bug 53967, several key agorithms (e.g. convolution) may execute \ 
much faster (e.g. 2-3X) for x86-64 and/or when SSE is enabled for floating point \ 
math (-mfpmath=sse) if the GCC option -frename-registers is used. Default 32-bit \ 
builds do not experience the problem since they use '387 math. It is not clear \ 
in what version of GCC this problem started but it was not noticed by the \ 
developers until the GCC 4.6 timeframe. Other compilers do not suffer from this \ 
bug. Please lobby the GCC project to fix this embarrassing performance bug.

Security Fixes:
* ScaleImage(): While not strictly a security issue, requesting to scale an \ 
image while retaining the original number of rows will lead to a program crash \ 
or memory corruption due to double-free.

Bug fixes:
* ScaleImage(): Fix problem with new width/height match original (regression \ 
added by 1.3.22).
* ScaleImage(): Fix double-free when new rows matches original rows (regression \ 
added by 1.3.22).
* MinGW build fix related to eliminating a sleep() macro which conflicts with a \ 
MinGW-provided inline sleep() function.
* PNG: Issue a warning instead of an error when attempting to read a PNG file \ 
containing a zero-length profile. This allows the file to be read.
* identify: Fix problem in that identify -format "%A" (to test if \ 
transparency is supported in image) does not always produce the correct results.