Issue Homebrew/homebrew#2950 mentions that the C++ lib was disabled because it caused LLVM
builds to fail. GraphicsMagick has since been flagged as `fails_with_llvm` so
this is a moot point and the increase in build time is negligible. A
`--without-magick-plus-plus` option has been added in case people want a lean
build.
Also removed ENV.O3 since it is pointless when `fails_with_llvm` is in effect.
Replaced ENV.gcc_4_2 + comments with calls to "fails_with_llvm",
to specifically message to the user when a formula is known or suspected
to not build with LLVM. If the user specifies "--use-llvm", the message
will be displayed, but compilation will be tried anyway.
Since using LLVM is now an advanced/hidden feature instead of the
default on 10.6, we'll let the user try anyway (and submit patches
if things are now working.)
GraphicsMagick was derived from ImageMagick, because they share a lot of setup
code. But keeping the ImageMagick formula up-to-date means breaking this one,
so I separated them.
GraphicsMagick provides a set of commandline tools and programming
APIs (including C, C++, Perl, and Tcl) for manipulating, editing,
and converting raster and vector images. GraphicsMagick is a fork
of ImageMagick, emphasizing stability of both programming API and
command-line options.
