Update GCC to 4.9.2

Update the GCC compiler to the 4.9.2 version.  It turns out that a C++
compiler is required to build the latest GCC releases, so build one in
stages 1 and 2 as well.

The updated list of GCC configuration options that either don't work in
a cross compiler or are not needed in a temporary compiler, were based
on the latest instructions from Linux From Scratch.

The inclusion of /lib64 in the lib path for the stage 1 linker is an
attempt to turn things more robust rather than to just symlink in /lib
stuff that ends up installed in /lib64 (as it is already being done for
libgcc_s.so).  Ideally, we should configure every chunk to install to
/lib, however GCC seems to not honour the `--with-libdir` configuration
flag.

With this version of GCC, it looks like a sysroot needs to be given at
configure time so that `--with-native-system-header-dir` does what it
claims to do.  Unfortunately, this has the side effect of making GCC not
passing to the linker the linker sysroot flag: `-Wl,--sysroot=$SYSROOT`.
The workaround is to modify LDFLAGS to give a sysroot directly to GCC,
`--sysroot=$SYSROOT`, which will then be further passed down to the
linker.

As the newest version of GCC finds more warnings than the previous one,
`-Werror` was disabled for the coreutils, GDB and Syslinux projects.
Syslinux's Makefile had to be patched, as it is not possible to disable
`-Werror` for all targets through the NO_WERROR variable.

The hack to handle libgcc_eh being required during eglibc's build was
removed, as it doesn't seem to be the case anymore.

1 files changed, 11 insertions, 18 deletions

diff --git a/strata/build-essential/gcc.morph b/strata/build-essential/gcc.morph
index 63d4ad4c..3b4b5ece 100644
--- a/strata/build-essential/gcc.morph
+++ b/strata/build-essential/gcc.morph
@@ -8,32 +8,25 @@ configure-commands:
 #   1. An attempt to stop anything going in $PREFIX/lib64 (which doesn't
 #      fully work; we will need to hobble the multilib configuration in
 #      config/i386/t-linux64 if we really want to kill /lib64).
-#   2. MPFR is built in the GCC tree, we need to locate it.
-#   3. Avoid having more than one copy of ZLib in use on the system
-#   4. Optimisation libraries which for now we do without.
-#   5. Multilib does not make sense in Baserock.
-#   6. Recommended by Linux From Scratch; required for C++ ABI
-#      compatibility with other Linux distributions.
+#   2. Avoid having more than one copy of ZLib in use on the system
+#   3. Multilib does not make sense in Baserock.
 - |
   cd o && ../configure                                        \
             $(../morph-arch-config)                           \
             --prefix="$PREFIX"                                \
     `# [1]` --libdir=$PREFIX/lib                              \
-    `# [2]` --with-mpfr-include="$(pwd)/../mpfr/src"          \
-    `# [2]` --with-mpfr-lib="$(pwd)/mpfr/src/.libs"           \
-    `# [3]` --with-system-zlib                                \
-    `# [4]` --without-cloog                                   \
-    `# [4]` --without-ppl                                     \
-            --disable-nls                                     \
-    `# [5]` --disable-multilib                                \
-            --disable-libgomp                                 \
-    `# [6]` --enable-__cxa_atexit                             \
-            --enable-shared                                   \
-            --enable-threads=posix                            \
+            --disable-bootstrap                               \
+    `# [2]` --with-system-zlib                                \
+    `# [3]` --disable-multilib                                \
             --enable-languages=c,c++,fortran
 
 build-commands:
-- cd o && make
+- |
+  case "$MORPH_ARCH" in
+      armv7*)   sed -i "s/--host=none/--host=armv7a/" o/Makefile
+                sed -i "s/--target=none/--target=armv7a/" o/Makefile ;;
+  esac
+  cd o && make
 
 install-commands:
 - cd o && make DESTDIR="$DESTDIR" install