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2367b02642
arch/m68k/Makefile computes lots of unneeded cc-option calls. For example, if CONFIG_M5441x is not defined, there is not point in evaluating the following compiler flag. cpuflags-$(CONFIG_M5441x) := $(call cc-option,-mcpu=54455,-mcfv4e) The result is set to cpuflags-, then thrown away. The right hand side of ':=' is immediately expanded. Hence, all of the 16 calls for cc-option are evaluated. This is expensive since cc-option invokes the compiler. This occurs even if you are not attempting to build anything, like 'make ARCH=m68k help'. Use '=' to expand the value _lazily_. The evaluation for cc-option is delayed until $(cpuflags-y) is expanded. So, the cc-option test happens just once at most. This commit mimics tune-y of arch/arm/Makefile. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Acked-by: Greg Ungerer <gerg@linux-m68k.org> Link: https://lore.kernel.org/r/20200526123810.301667-3-masahiroy@kernel.org Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
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.