Re: [Qemu-devel] [PATCH] docker: Don't use eval trick on Makefile

[Peter Maydell]

On 7 June 2016 at 04:24, Fam Zheng <address@hidden> wrote:
> On Mon, 06/06 12:53, Eduardo Habkost wrote:
>> The eval trick for defining DOCKER_SRC_COPY doesn't do anything
>> useful, as DOCKER_SRC_COPY is immediately expanded just after it
>> is defined, and CUR_TIME is already defined using ":=". Simply
>> define it using ":=" so it is evaluated only once.
>>
>> The eval trick was also triggering an weird error on Travis builds:
>>   qemu/tests/docker/Makefile.include:34: *** unterminated variable 
>> reference.  Stop.
>>
>> The issue is not easily reproducible (maybe it's a bug in some
>> versions of Make), but it is avoided if removing the eval trick.
>>
>> Signed-off-by: Eduardo Habkost <address@hidden>
>> ---
>>  tests/docker/Makefile.include | 3 +--
>>  1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/tests/docker/Makefile.include b/tests/docker/Makefile.include
>> index 2fd2ca3..134dc6f 100644
>> --- a/tests/docker/Makefile.include
>> +++ b/tests/docker/Makefile.include
>> @@ -28,8 +28,7 @@ make-archive-maybe = $(if $(wildcard $1/*), \
>>               "  ARCHIVE $(notdir $2)"))
>>
>>  CUR_TIME := $(shell date +%Y-%m-%d-%H.%M.%S.$$$$)
>> -# Makes the definition constant after the first expansion
>> -DOCKER_SRC_COPY = $(eval DOCKER_SRC_COPY := 
>> docker-src.$(CUR_TIME))$(DOCKER_SRC_COPY)
>> +DOCKER_SRC_COPY := docker-src.$(CUR_TIME)
>>
>>  $(DOCKER_SRC_COPY):
>>       @mkdir $@
>> --
>> 2.5.5
>>
>
> Applied, thanks.

Hi; I'd like to apply this direct to master, because one of my build
test machines hits this error intermittently, and so without the fix
I can't reliably process any other pull requests.

thanks
-- PMM