[libvirt] [PATCH] tests: improve build time for qemuxml2argvtest

[Daniel Henrique Barboza]

On 11/27/19 1:22 PM, Daniel P. Berrangé wrote:
> On Fedora 31 with GCC 9.2.1, compiling qemuxml2argvtest takes
> about 36 seconds since
> 
>    commit 30c6d99209cd36bba8e14795622f658827698522
>    Author: Jiri Denemark <jdenemar at redhat.com>
>    Date:   Thu Oct 24 17:51:42 2019 +0200
> 
>      qemuxml2argvtest: Update host arch for DO_TEST*ARCH* tests
> 
> The optimizer is hitting some pathelogical performance behaviour due to
> the high number of branches in the mymain() method.
> 
> Pushing the branch tests down into the testCompareXMLToArgv method
> brings the compile time down to 3 seconds.
> 
> Signed-off-by: Daniel P. Berrangé <berrange at redhat.com>
> ---


In my Fedora 31 box, 'make' time of qemuxml2argvtest.c with this patch:

real	0m4.113s
user	0m3.838s
sys	0m0.360s


Without it:


real	0m35.099s
user	0m34.573s
sys	0m0.544s



Reviewed-by: Daniel Henrique Barboza <danielhb413 at gmail.com>