Bug 1386588 - Add a toolchain job for GCC 4.8, and build clang agains…

…t it. r=gps

While this looks like going backwards, it is desirable to build clang
against GCC 4.8, such that it contains its libgcc. This, in turn, will
solve problems using clang 3.9 with static-analysis builds (details in
bug 1356926). Another way to fix those problems would be to build clang
3.8 but that too would require GCC 4.8. Upgrading those builds to clang
3.9 will also allow to enable stylo on them.

taskcluster/ci/toolchain/linux.yml

@@ -23,7 +23,7 @@ linux64-clang-3.9:
         toolchain-alias: linux64-clang
         toolchain-artifact: public/build/clang.tar.xz
     toolchains:
-        - linux64-gcc
+        - linux64-gcc-4.8
 
 linux64-clang-tidy:
     description: "Clang-tidy build"
@@ -51,6 +51,24 @@ linux64-clang-tidy:
     toolchains:
         - linux64-gcc
 
+linux64-gcc-4.8:
+    description: "GCC 4.8 toolchain build"
+    treeherder:
+        kind: build
+        platform: toolchains/opt
+        symbol: TL(gcc4.8)
+        tier: 1
+    worker-type: aws-provisioner-v1/gecko-{level}-b-linux
+    worker:
+        docker-image: {in-tree: desktop-build}
+        max-run-time: 36000
+    run:
+        using: toolchain-script
+        script: build-gcc-4.8-linux.sh
+        resources:
+            - 'build/unix/build-gcc/build-gcc.sh'
+        toolchain-artifact: public/build/gcc.tar.xz
+
 linux64-gcc-4.9:
     description: "GCC 4.9 toolchain build"
     treeherder:

taskcluster/scripts/misc/build-gcc-4.8-linux.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+set -e
+
+# This script is for building GCC 4.8 for Linux.
+
+WORKSPACE=$HOME/workspace
+HOME_DIR=$WORKSPACE/build
+UPLOAD_DIR=$HOME/artifacts
+
+root_dir=$HOME_DIR
+data_dir=$HOME_DIR/src/build/unix/build-gcc
+
+. $data_dir/build-gcc.sh
+
+gcc_version=4.8.5
+gcc_ext=bz2
+binutils_version=2.25.1
+binutils_ext=bz2
+
+# GPG key used to sign GCC
+$GPG --import $data_dir/13975A70E63C361C73AE69EF6EEB81F8981C74C7.key
+# GPG key used to sign binutils
+$GPG --import $data_dir/EAF1C276A747E9ED86210CBAC3126D3B4AE55E93.key
+# GPG key used to sign GMP
+$GPG --import $data_dir/343C2FF0FBEE5EC2EDBEF399F3599FF828C67298.key
+# GPG key used to sign MPFR
+$GPG --import $data_dir/07F3DBBECC1A39605078094D980C197698C3739D.key
+# GPG key used to sign MPC
+$GPG --import $data_dir/AD17A21EF8AED8F1CC02DBD9F7D5C9BF765C61E3.key
+
+cat > $HOME_DIR/checksums <<EOF
+b5b14added7d78a8d1ca70b5cb75fef57ce2197264f4f5835326b0df22ac9f22  binutils-2.25.1.tar.bz2
+22fb1e7e0f68a63cee631d85b20461d1ea6bda162f03096350e38c8d427ecf23  gcc-4.8.5.tar.bz2
+752079520b4690531171d0f4532e40f08600215feefede70b24fabdc6f1ab160  gmp-5.1.3.tar.bz2
+ae79f8d41d8a86456b68607e9ca398d00f8b7342d1d83bcf4428178ac45380c7  mpc-0.8.2.tar.gz
+ca498c1c7a74dd37a576f353312d1e68d490978de4395fa28f1cbd46a364e658  mpfr-3.1.5.tar.bz2
+EOF
+
+prepare
+apply_patch $data_dir/PR64905.patch
+build_binutils
+build_gcc
+
+# Put a tarball in the artifacts dir
+mkdir -p $UPLOAD_DIR
+cp $HOME_DIR/gcc.tar.* $UPLOAD_DIR