Move clang intallation from prerequisites.sh to systools/clang.sh. Remove gcc-4.9 and gcc-4.8 unneeded installation.

toolset/setup/linux/frameworks/silicon.sh

@@ -1,5 +1,7 @@
 #!/bin/bash
 
+fw_depends clang
+
 RETCODE=$(fw_exists ${IROOT}/silicon.installed)
 [ ! "$RETCODE" == 0 ] || { \
   # Load environment variables

toolset/setup/linux/prerequisites.sh

@@ -63,17 +63,6 @@ sudo pip install colorama==0.3.1
 sudo pip install progressbar==2.2
 sudo pip install requests
 
-# Install gcc-4.8, gcc-4.9
-sudo add-apt-repository ppa:ubuntu-toolchain-r/test -y
-sudo apt-get -yq update
-sudo apt-get install -qqy gcc-4.8 g++-4.8 gcc-4.9 g++-4.9
-
-# Install Clang, needed by silicon.
-sudo add-apt-repository -s "deb http://apt.llvm.org/`lsb_release -cs`/ llvm-toolchain-`lsb_release -cs`-3.8 main"
-wget -O - http://apt.llvm.org/llvm-snapshot.gpg.key|sudo apt-key add -
-sudo apt-get -yq update
-sudo apt-get install -qqy clang-3.8
-
 # Stop permanently overwriting people's files just for 
 # trying out our software!
 RETCODE=$(fw_exists ~/.bash_profile.bak)

toolset/setup/linux/systools/clang.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+
+RETCODE=$(fw_exists ${IROOT}/clang.installed)
+[ ! "$RETCODE" == 0 ] || { \
+  source $IROOT/clang.installed
+  return 0; }
+
+sudo add-apt-repository -s "deb http://apt.llvm.org/`lsb_release -cs`/ llvm-toolchain-`lsb_release -cs`-3.8 main"
+wget -O - http://apt.llvm.org/llvm-snapshot.gpg.key|sudo apt-key add -
+sudo apt-get -yq update
+sudo apt-get install -qqy clang-3.8
+
+touch $IROOT/clang.installed