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Arnout Vandecappelle 7d69a79624 packages: use backtick instead of $(shell ...) make function
It is often difficult to know exactly when make will expand the
variable, and usually it can only be expanded after the dependencies
have been built (e.g. pkg-config or the .pc file). Using a backtick
instead makes it very clear that it will be expanded only while
executing the command.

This change is useful for two cases:

1. The per-package staging (and host) directory will be created as part
   of the configure step, so any $(shell ...) variable that is used in
   the configure step will fail because the directory doesn't exist
   yet.

2. 'make printvars' evaluates the variables it prints. It will therefore
   trigger a lot of errors from missing .pc files and others. The
   backticks, on the other hand, are not expanded, so with this change
   the output of 'make printvars' becomes clean again.

This commit contains only the easy changes: replace $(shell ...) with
`...`, and also replace ' with " where needed. Follow-up commits will
tackle the more complicated cases that need additional explanation.

After this change, the following instances of $(shell ...) will remain:

- All assignments that use :=
- All variables that are used in make conditionals (which don't expand
  the backticks).
- All variables that only refer to system executables and make
  variables that don't change.
- The calls to check-host-* in dependencies.mk, because it is eval'ed.

[Original patch by Fabio Porcedda, but extended quite a bit by Arnout.]

Signed-off-by: Fabio Porcedda <fabio.porcedda@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2015-07-15 00:42:01 +02:00
arch
board
boot boot/uboot: Add support for dtb.img format 2015-07-15 00:06:04 +02:00
configs
docs docs/manual: Fix trivial typo 2015-07-14 23:56:58 +02:00
fs
linux package/perf: migrate perf to use the new linux-tools infrastructure 2015-07-14 23:28:06 +02:00
package packages: use backtick instead of $(shell ...) make function 2015-07-15 00:42:01 +02:00
support graph-depends: Strip skeleton from dependency 2015-07-14 18:10:58 +02:00
system skeleton: New package 2015-07-14 18:08:23 +02:00
toolchain toolchain-external: fix support of uClibc-ng toolchains 2015-07-14 10:07:55 +02:00
.defconfig
.gitignore
CHANGES
Config.in core: fix download menu 2015-07-14 09:46:51 +02:00
Config.in.legacy package/perf: migrate perf to use the new linux-tools infrastructure 2015-07-14 23:28:06 +02:00
COPYING
Makefile Makefile: save MAKE_VERSION 2015-07-14 23:53:21 +02:00
Makefile.legacy
README

Buildroot is a simple, efficient and easy-to-use tool to generate embedded
Linux systems through cross-compilation.

The documentation can be found in docs/manual. You can generate a text
document with 'make manual-text' and read output/docs/manual/manual.text.
Online documentation can be found at http://buildroot.org/docs.html

To build and use the buildroot stuff, do the following:

1) run 'make menuconfig'
2) select the target architecture and the packages you wish to compile
3) run 'make'
4) wait while it compiles
5) find the kernel, bootloader, root filesystem, etc. in output/images

You do not need to be root to build or run buildroot.  Have fun!

Buildroot comes with a basic configuration for a number of boards. Run
'make list-defconfigs' to view the list of provided configurations.

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