Option to disable RVO via PHALCON_NO_RVO environment variable
Fix segfault in zim_Phalcon_Image_Adapter_GD_check
Merge pull request #1147 from sjinks/optional-rvo

[NFR] Option to disable RVO at run time
Merge pull request #1149 from sjinks/image-crash

[BUG] [CRASH] Segmentation fault in Phalcon\Image\Adapter\Gd::check()