[0/3] build: honor toolchain related environment vars

Message

Roger Pau Monné July 26, 2019, 1:33 p.m. UTC

Hello,

Current Xen build system will ignore any toolchain related variables on
the environment when building (ie: CC, LD, CXX...), and the only way to
set those is to assign them directly on the make command line (ie: make
CC=foo CXX=bar ...).

The following series attempts to fix this, by removing the hardcoding of
the toolchain variables previously done in StdGNU.mk.

Note that this has the side effect that the build system will no longer
prepend CROSS_COMPILE to the toolchain variables if those are already
set. So if you are building Xen and setting CROSS_COMPILE make sure
toolchain variables are unset, or if set they should contain
CROSS_COMPILE. The Travis CI script is updated in patch 2/3 in order to
comply with the above.

The series can be found at:

git://xenbits.xen.org/people/royger/xen.git env_tools.wip

Results from Travis and gitlab CI loops are at:

https://travis-ci.org/royger/xen/builds/563972832
https://gitlab.com/xen-project/people/royger/xen/pipelines/73130338

Thanks, Roger.

Roger Pau Monne (3):
  kconfig: include default toolchain values
  build: allow picking the env values for compiler variables
  build: allow picking the env values for toolchain utilities

 config/StdGNU.mk                   | 55 ++++++++++++++++--------------
 scripts/travis-build               |  8 +++++
 xen/Makefile                       |  6 ++--
 xen/tools/kconfig/Makefile.kconfig |  7 ++--
 4 files changed, 43 insertions(+), 33 deletions(-)