Fix assigning default compiler if CC is unset

dependency_setup.sh

@@ -1,6 +1,5 @@
 #! /bin/bash
 script_root=$(pwd)
-CC:="clang"
 
 echo "Creating folder for libraries"
 mkdir lib
@@ -12,7 +11,7 @@ git clone https://h2939863.stratoserver.net/git/XOR/simple_hashtable.git
 cd simple_hashtable
 
 echo "Building simple_hashtable library"
-$CC -c shash.c -o $script_root/lib/shash.o
+${CC:=clang} -c shash.c -o $script_root/lib/shash.o
 
 echo "Delete source files"
 cd $script_root