deivid-rodriguez/byebug — pull request #22 by eagletmt (2013-09-14 05:23:24+00:00)
Title: Honor RbConfig::MAKEFILE_CONFIG['CFLAGS']

mkmf sets `$CFLAGS` from `RbConfig::MAKEFILE_CONFIG['CFLAGS']` by default, and it should be preserved to build extensions properly.