AD ME ▁further ▁points ▁at ▁a ▁rewrite ▁in ▁ 1 9 9 3 ▁( G CC ▁ 2 . 4 ). ▁ ▁The ▁Ne XT ▁front end ▁source ▁code ▁was ▁released ▁since ▁it ▁was ▁made ▁as ▁part ▁of ▁G CC , ▁released ▁GNU ▁Public ▁License ▁which ▁forces ▁ones ▁making ▁derivative ▁works ▁to ▁do ▁so . ▁Apple ▁continued ▁this ▁tradition ▁in ▁re le asing ▁its ▁fork ▁of ▁G CC ▁up ▁to ▁ 4 . 2 . 1 , ▁after ▁which ▁they ▁abandoned ▁the ▁compiler . ▁G CC ▁maintain ers ▁took ▁in ▁the ▁changes , ▁but ▁did ▁not ▁invest ▁much ▁in ▁supporting ▁newer ▁features ▁such ▁as ▁the ▁Object ive - C ▁ 2 . 0 ▁language . ▁ ▁The ▁GNU step ▁developers , ▁interested ▁in ▁the ▁new ▁language , ▁for ked ▁the ▁G CC ▁ ▁to ▁a ▁project ▁independent ▁of ▁G CC ▁called ▁ ▁in ▁ 2 0 0 9 . ▁They ▁also ▁arranged ▁for ▁the ▁runtime ▁to ▁be ▁used ▁with ▁Cl ang ▁to ▁take ▁advantage ▁of ▁the ▁new ▁language ▁syntax . ▁G CC ▁moved ▁slowly ▁at ▁the ▁same ▁time , ▁but ▁at ▁G CC ▁ 4 . 6 . 0 ▁( 2 0 1 1 ) ▁they ▁have ▁moved ▁on ▁to ▁Object ive - C ▁ 2 . 0 ▁in ▁their ▁lib obj c ▁as ▁well . ▁GNU step ▁documentation ▁suggest ▁that ▁the ▁G CC ▁implementation ▁still ▁la cks ▁support ▁for ▁blocks , ▁non - f rag ile ▁variables , ▁and ▁the ▁newer ▁AR C . ▁ ▁Microsoft ▁for ked ▁ ▁into ▁a ▁part