* update

* update

* fix empty arg

* update test

* update

* fix bug

* update

* update

* repalce gflags header

* replace DEFINE_<type> with PD_DEFINE_<type>

* fix bug

* fix bug

* fix bug

* update cmake

* add :: before some paddle namespace

* fix link error

* fix CI-Py3

* allow commandline parse

* fix SetFlagsFromEnv

* fix bug

* fix bug

* fix CI-CINN

* fix CI-Coverage-build

* fix CI-Windows-build

* fix CI-Inference

* fix bug

* fix bug

* fix CI-CINN

* fix inference api test

* fix infer_ut test

* revert infer_ut gflags usage

* update

* fix inference

* remove flags export macro

* revert inference demo_ci gflags usage

* update

* update

* update

* update

* update

* update

* update

* update

* fix bug when turn on WITH_GFLAGS

* turn on WITH_GFLAGS

* fix bug when turn on WITH_GFLAGS

* fix bug when turn on WITH_GFLAGS

* update

* update and add unittest

* add unittest

* fix conflict

* rerun ci

* update

* resolve conflict