The logic added in commit v3.6.0-rc1~30^2 (Add a variable to specify
language-wide system include directories, 2016-05-24) to use
`CMAKE_<LANG>_STANDARD_INCLUDE_DIRECTORIES` incorrectly filters them by
`CMAKE_<LANG>_IMPLICIT_INCLUDE_DIRECTORIES`. Rather than recognizing
this, commit v3.8.0-rc1~60^2 (Android: Pass sysroot include directory
explicitly, 2017-01-20) worked around the problem by incorrectly
removing `/usr/include` from `CMAKE_<LANG>_IMPLICIT_INCLUDE_DIRECTORIES`
so it worked in `CMAKE_<LANG>_STANDARD_INCLUDE_DIRECTORIES`.
By not filtering out `/usr/include` from user-specified include
directories, we allow the code
include_directories(${CMAKE_SYSROOT}/usr/include)
to place the include directory too early on the command line.
Fix support for standard include directories to not be filtered by
implicit include directories, and do not remove `/usr/include` from the
list of implicit include directories for Android builds. Add a test
case to verify that an explicit `/usr/include` is ignored in favor
of the standard directory at the end.
Fixes: #17059
Expose the binutils' machine name (typically used as a prefix on the
tool names) publicly. This is expected to match the `gcc -dumpmachine`
value.
Suggested-by: Ruslan Baratov <ruslan_baratov@yahoo.com>
The NDK provides prebuilt toolchain files in directories named for the
host architecture. The NDK build system calls this `HOST_TAG`.
Expose the value publicly for use by clients that need to pass it
to external tools.
Suggested-by: Ruslan Baratov <ruslan_baratov@yahoo.com>
When this variable is not set by the user or toolchain file, set it to
the default selected. This will be useful for client code that needs to
pass the value to an external tool that needs to find the same toolchain
in the NDK. Leave it empty for a standalone toolchain.
Suggested-by: Ruslan Baratov <ruslan_baratov@yahoo.com>
We use `-Werror` in the Android test builds to make sure there are
no warnings that we care about (e.g. unused flags). However, the
NDK r13 tools produce a warning about their own builtins:
```
<built-in>: In function 'float abs(float)':
<built-in>: warning: conflicts with previous declaration here [-Wattributes]
```
Suppress this warning so that we can continue using `-Werror` but
tolerate these warnings.
