Masahiro Yamada
b066e9ee99
[ Upstream commit f2f02ebd8f ]
When cc-option and friends evaluate compiler flags, the temporary file
$$TMP is created as an output object, and automatically cleaned up.
The actual file path of $$TMP is .<pid>.tmp, here <pid> is the process
ID of $(shell ...) invoked from cc-option. (Please note $$$$ is the
escape sequence of $$).
Such garbage files are cleaned up in most cases, but some compiler flags
create additional output files.
For example, -gsplit-dwarf creates a .dwo file.
When CONFIG_DEBUG_INFO_SPLIT=y, you will see a bunch of .<pid>.dwo files
left in the top of build directories. You may not notice them unless you
do 'ls -a', but the garbage files will increase every time you run 'make'.
This commit changes the temporary object path to .tmp_<pid>/tmp, and
removes .tmp_<pid> directory when exiting. Separate build artifacts such
as *.dwo will be cleaned up all together because their file paths are
usually determined based on the base name of the object.
Another example is -ftest-coverage, which outputs the coverage data into
<base-name-of-object>.gcno
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.