* Don't encode "-Qunused-arguments", as this is only supported in Clang
and will break building when C/C++ compiler is switched during the
process, e.g. building gcc. The warning is harmless without
"-Werror".
* Add new ENV function for selecting stdlib for Clang.
- The selection is no-op for non-system-clang compilers.
- Both superenv and stdenv are handled.
* Add new HOMEBREW_CCCFG flag and ccwrapper handling.
* Add options and ENV method to specify building in C++11 mode.
- Set C++ compiler flags to enable C++11 mode.
- To add options to support C++11 mode, a formula can now use
option :cxx11
to provide "--c++11" option, and detect and enable C++11 support in
install method using
ENV.cxx11 if build.cxx11?
ClosesHomebrew/homebrew#22453.
If an etc file exists on installation instead of overwriting it (or
requiring all the manual checks in formula) simply copy it with the
extension `.default` appended.
After a formula is built, scan all mach-o files for dynamic links
to see if any of them point to a C++ stdlib (libc++ or libstdc++).
If one of them is linked, record that information in the formula's tab.
This replaces the old behaviour where all files were assumed to be C++
code, and stdlibs were always tracked regardless of whether they were
actually linked against.
This also modifies the way that tabs are written - now tabs are written
with the stdlib field null, and values are only written if an stdlib
is detected.
If @compiler isn't set/checked by ENV.compiler and the ENV.clang/etc.
methods, ENV.compiler may return unexpected results after fails_with
picks a fallback compiler.
See Homebrew/homebrew#22674.
This moves the CompilerSelector fails_with logic into the build
environment setup, making the compiler selection available before
performing actions that depends on knowing what the compiler is, e.g.
setting up PATH.
ENV.setup_build_environment now optionally takes a Formula argument
to provide the information necessary to do the fails_with, and the new
ENV.validate_cc! extracts the fails_with logic from Build.install.
ENV.compiler is called outside setting up the build environment, where
values unsupported for user input might have been specified - for
example, GNU GCC executables.
This adds support for non-Apple GCC compilers in the fails_with code.
A fails_with block for a non-Apple compiler looks like:
fails_with :gcc => '4.8.1' do
cause 'Foo'
end
Non-Apple compilers don't have build numbers, so compiler failures are
based on version strings instead.
Internally non-Apple compilers can be distinguished because they are
passed around as strings instead of symbols.
In addition, this alters the priority list for compilers, with the
following changes:
* Apple GCC 4.2 and LLVM-GCC swap positions, with GCC now taking
priority. (Maybe LLVM-GCC should just go away.)
* Non-Apple GCC compilers are ranked below GCC 4.2 but above LLVM-GCC
and Apple GCC 4.0.
This unifies the logic for selecting a compiler between superenv and
stdenv. A variation of superenv's `determine_cc`, which now returns a
symbol, has been moved into the shared ENV extension. Stdenv uses the
result of this directly (as it's always used symbols), while superenv
translates that back into a compiler string.
This also has the effect of disabling HOMEBREW_USE_(gcc|llvm|clang) in
stdenv, which have already been marked as deprecated for some time, and
enables the HOMEBREW_CC= environment variable syntax from superenv in
stdenv.
This allows overriding the "oldest CPU" behaviour - for instance, to
build Intel bottles for a newer CPU than Core 2, to build a PPC bottle
with or without Altivec on the same computer, etc.
