Bug 32355: gcc: Add linux-arm target

projects/gcc/build

@@ -16,11 +16,85 @@
   # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48817.
   export DEB_BUILD_HARDENING_FORMAT=0
 [% END -%]
-distdir=/var/tmp/dist/[% project %]
+distdir=/var/tmp/dist/[% c("var/distdir") %]
 mkdir /var/tmp/build
-tar -C /var/tmp/build -xf $rootdir/[% c('input_files_by_name/gcc') %]
-cd /var/tmp/build/[% project %]-[% c("version") %]
-./configure --prefix=$distdir [% c("var/configure_opt") %]
+
+[% IF c("var/linux-cross") -%]
+
+  # Install binutils (needed for cross-compiling)
+  mkdir /var/tmp/dist
+  cd /var/tmp/dist
+  tar xf $rootdir/[% c('input_files_by_name/binutils') %]
+  mv binutils $distdir
+  export PATH="$distdir/bin:$PATH"
+
+  # Install Linux headers, see Step 2 of
+  # https://preshing.com/20141119/how-to-build-a-gcc-cross-compiler/
+  # Doing this before gcc configure is intended to solve a limits.h issue
+  cd /var/tmp/build
+  mkdir linux
+  cd linux
+  tar -xJf $rootdir/linux-[% c("var/linux_version") %].tar.xz
+  cd linux-[% c("var/linux_version") %]
+  make ARCH=[% c("arch") %] INSTALL_HDR_PATH=$distdir/[% c("var/crosstarget") %] headers_install
+
+  cd /var/tmp/build
+  mkdir gcc
+  cd gcc
+  tar -xJf $rootdir/[% c('input_files_by_name/gcc') %]
+  # --with-headers is intended to solve a limits.h issue
+  [% project %]-[% c("version") %]/configure --prefix=$distdir --with-headers=$distdir/[% c("var/crosstarget") %]/include/linux [% c("var/configure_opt") %]
+
+  # For cross-compiling to work, we need to partially build GCC, then build
+  # glibc, then come back to finish GCC.
+
+  # Build only the components of GCC that don't need glibc, see Step 3 of
+  # https://preshing.com/20141119/how-to-build-a-gcc-cross-compiler/
+  cd /var/tmp/build/gcc
+  make -j[% c("num_procs") %] all-gcc
+  make install-gcc
+  # Removing sys-include is intended to solve a limits.h issue
+  rm --recursive --force $distdir/[% c("var/crosstarget") %]/sys-include
+
+  # Build glibc headers and startup files, see Step 4 of
+  # https://preshing.com/20141119/how-to-build-a-gcc-cross-compiler/
+  cd /var/tmp/build
+  mkdir glibc
+  cd glibc
+  tar -xJf $rootdir/glibc-[% c("var/glibc_version") %].tar.xz
+  # TODO: Remove --disable-werror once glibc is upgraded to a version that's
+  # designed to work with the GCC version we're using.
+  glibc-[% c("var/glibc_version") %]/configure --prefix=$distdir/[% c("var/crosstarget") %] --build=$MACHTYPE --host=[% c("var/crosstarget") %] --target=[% c("var/crosstarget") %] --with-headers=$distdir/[% c("var/crosstarget") %]/include --disable-multilib --disable-werror libc_cv_forced_unwind=yes
+  make install-bootstrap-headers=yes install-headers
+  make -j[% c("num_procs") %] csu/subdir_lib
+  install csu/crt1.o csu/crti.o csu/crtn.o $distdir/[% c("var/crosstarget") %]/lib
+  [% c("var/crosstarget") %]-gcc -nostdlib -nostartfiles -shared -x c /dev/null -o $distdir/[% c("var/crosstarget") %]/lib/libc.so
+  # stdio_lim.h is intended to solve a limits.h issue
+  touch $distdir/[% c("var/crosstarget") %]/include/gnu/stubs.h $distdir/[% c("var/crosstarget") %]/include/bits/stdio_lim.h
+
+  # Build compiler support library, see Step 5 of
+  # https://preshing.com/20141119/how-to-build-a-gcc-cross-compiler/
+  cd /var/tmp/build/gcc
+  make -j[% c("num_procs") %] all-target-libgcc
+  make install-target-libgcc
+
+  # finish building glibc, see Step 6 of
+  # https://preshing.com/20141119/how-to-build-a-gcc-cross-compiler/
+  cd /var/tmp/build/glibc
+  make -j[% c("num_procs") %]
+  make install
+
+  # We're done with glibc, we can now finish building gcc...
+  cd /var/tmp/build/gcc
+
+[% ELSE -%]
+
+  tar -C /var/tmp/build -xf $rootdir/[% c('input_files_by_name/gcc') %]
+  cd /var/tmp/build/[% project %]-[% c("version") %]
+  ./configure --prefix=$distdir [% c("var/configure_opt") %]
+
+[% END -%]
+
 make -j[% c("num_procs") %]
 make install
 # tor-browser-build#31321: we need a link to our GCC, to prevent some projects
@@ -28,6 +102,6 @@ make install
 ln -s gcc $distdir/bin/cc
 cd /var/tmp/dist
 [% c('tar', {
-        tar_src => [ project ],
+        tar_src => [ c('var/distdir') ],
         tar_args => '-czf ' _ dest_dir _ '/' _ c('filename'),
         }) %]

projects/gcc/config

@@ -7,14 +7,17 @@ version: '[% pc("gcc-source", "version") %]'
 container:
   use_container: 1
 var:
+  distdir: gcc
   deps:
     - build-essential
     - libmpc-dev
   setup: |
     mkdir -p /var/tmp/dist
     tar -C /var/tmp/dist -xf $rootdir/[% c("compiler_tarfile") %]
-    export PATH="/var/tmp/dist/gcc/bin:$PATH"
-    export LD_LIBRARY_PATH=/var/tmp/dist/gcc/lib64:/var/tmp/dist/gcc/lib32
+    export PATH="/var/tmp/dist/[% c("var/distdir") %]/bin:$PATH"
+    [% IF ! c("var/linux-cross") -%]
+      export LD_LIBRARY_PATH=/var/tmp/dist/[% c("var/distdir") %]/lib64:/var/tmp/dist/[% c("var/distdir") %]/lib32
+    [% END -%]
 
     [% IF c("hardened_gcc") -%]
       # Config options for hardening-wrapper
@@ -25,14 +28,14 @@ var:
       export DEB_BUILD_HARDENING_PIE=1
 
       # Make sure we use the hardening wrapper
-      pushd /var/tmp/dist/gcc/bin
+      pushd /var/tmp/dist/[% c("var/distdir") %]/bin
       cp /usr/bin/hardened-cc ./
-      mv gcc gcc.real
-      mv c++ c++.real
-      mv g++ g++.real
-      ln -sf hardened-cc gcc
-      ln -sf hardened-cc c++
-      ln -sf hardened-cc g++
+      mv [% c("var/target_prefix") %]gcc [% c("var/target_prefix") %]gcc.real
+      mv [% c("var/target_prefix") %]c++ [% c("var/target_prefix") %]c++.real
+      mv [% c("var/target_prefix") %]g++ [% c("var/target_prefix") %]g++.real
+      ln -sf hardened-cc [% c("var/target_prefix") %]gcc
+      ln -sf hardened-cc [% c("var/target_prefix") %]c++
+      ln -sf hardened-cc [% c("var/target_prefix") %]g++
       popd
     [% END -%]
 
@@ -50,8 +53,34 @@ targets:
       arch_deps:
         - hardening-wrapper
         - libc6-dev-i386
+  linux-cross:
+    var:
+      target_prefix: '[% c("var/crosstarget") %]-'
+      distdir: gcc-cross
+      # TODO: Consider upgrading to a glibc that works out of the box with the
+      # GCC version we use. However, removing our glibc version workarounds may
+      # not be desirable since we want to be able to easily bump the GCC
+      # version without worrying about linux-cross breakage.
+      glibc_version: 2.26
+      linux_version: 4.10.1
+      arch_deps:
+        - hardening-wrapper
+        - libc6-dev-i386
+        - gawk
+  linux-arm:
+    var:
+      configure_opt: --disable-multilib --enable-languages=c,c++ --target=arm-linux-gnueabihf --with-arch=armv7-a --with-fpu=vfpv3-d16 --with-float=hard --with-mode=thumb
 
 input_files:
   - project: container-image
   - project: gcc-source
     name: gcc
+  - name: binutils
+    project: binutils
+    enable: '[% c("var/linux-cross") -%]'
+  - URL: 'https://ftp.gnu.org/gnu/glibc/glibc-[% c("var/glibc_version") %].tar.xz'
+    sha256sum: e54e0a934cd2bc94429be79da5e9385898d2306b9eaf3c92d5a77af96190f6bd
+    enable: '[% c("var/linux-cross") -%]'
+  - URL: 'https://www.kernel.org/pub/linux/kernel/v4.x/linux-[% c("var/linux_version") %].tar.xz'
+    sha256sum: 6ca06bb5faf5f83600d7388bb623dae41df2a257de85ad5d1792e03302bc3543
+    enable: '[% c("var/linux-cross") -%]'