Bug 25304: update gcc to 6.4.0 for the Linux build

projects/gcc/build

@@ -6,7 +6,12 @@
   export DEB_BUILD_HARDENING=1
   export DEB_BUILD_HARDENING_STACKPROTECTOR=1
   export DEB_BUILD_HARDENING_FORTIFY=1
-  export DEB_BUILD_HARDENING_PIE=1
+  # Since r223796 landed on GCC master enforcing PIE breaks GCC compilation.
+  # The compiler gets built with `-fno-PIE` and linked with `-no-pie` as not
+  # doing so would make precompiled headers (PCH) fail.
+  # It is okay for us to omit this right now as it does not change any hardening
+  # flags in the resulting bundles.
+  export DEB_BUILD_HARDENING_PIE=0
   # We need to disable `-Werror=format-security` as GCC does not build with it
   # anymore. It seems it got audited for those problems already:
   # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48817.
@@ -14,7 +19,7 @@
 [% END -%]
 distdir=/var/tmp/dist/[% project %]
 mkdir /var/tmp/build
-tar -C /var/tmp/build -xf [% project %]-[% c("version") %].tar.bz2
+tar -C /var/tmp/build -xf [% project %]-[% c("version") %].tar.xz
 cd /var/tmp/build/[% project %]-[% c("version") %]
 ./configure --prefix=$distdir [% c("var/configure_opt") %]
 make -j[% c("buildconf/num_procs") %]

projects/gcc/config

 # vim: filetype=yaml sw=2
 filename: '[% project %]-[% c("version") %]-[% c("var/build_id") %].tar.gz'
-version: 5.4.0
+version: 6.4.0
 var:
   container:
     use_container: 1
@@ -58,5 +58,5 @@ targets:
         - libc6-dev-i386
 input_files:
   - project: container-image
-  - URL: 'https://ftp.gnu.org/gnu/gcc/gcc-[% c("version") %]/gcc-[% c("version") %].tar.bz2'
-    sha256sum: 608df76dec2d34de6558249d8af4cbee21eceddbcb580d666f7a5a583ca3303a
+  - URL: 'https://ftp.gnu.org/gnu/gcc/gcc-[% c("version") %]/gcc-[% c("version") %].tar.xz'
+    sha256sum: 850bf21eafdfe5cd5f6827148184c08c4a0852a37ccf36ce69855334d2c914d4

projects/tor/build

@@ -45,7 +45,7 @@ openssldir=/var/tmp/dist/openssl
   # 13359 for further details.
   cp /var/tmp/dist/gcc/[% c("var/libdir") %]/libstdc++.so.6 "$distdir/Tor/"
   [% IF c("var/asan") -%]
-    cp /var/tmp/dist/gcc/[% c("var/libdir") %]/libasan.so.2 "$distdir/Tor/"
+    cp /var/tmp/dist/gcc/[% c("var/libdir") %]/libasan.so.3 "$distdir/Tor/"
     cp /var/tmp/dist/gcc/[% c("var/libdir") %]/libubsan.so.0 "$distdir/Tor/"
   [% END -%]
   chmod 700 "$distdir"/Tor/*.so*