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, 4 insertions, 7 deletions

diff --git a/strata/build-essential/stage2-binutils.morph b/strata/build-essential/stage2-binutils.morph
index bc0b18ac..1c64fb29 100644
--- a/strata/build-essential/stage2-binutils.morph
+++ b/strata/build-essential/stage2-binutils.morph
@@ -5,20 +5,17 @@ build-system: autotools
 configure-commands:
 - |
   export STAGE2_SYSROOT="$(dirname $(pwd))"
-  export CPPFLAGS="--sysroot=$STAGE2_SYSROOT"
   export CXX=false
-  export LDFLAGS="-Wl,--sysroot=$STAGE2_SYSROOT"
+  # binutils has its own embedded libtool, which is old and strips out
+  # `--sysroot`.  Work around by modifying the compiler command to
+  # include the sysroot flag
+  export CC="$TARGET_STAGE1-gcc --sysroot=$STAGE2_SYSROOT"
   ./configure --prefix="$PREFIX" --disable-nls --disable-werror \
     --build=$(sh config.guess) \
     --host=$TARGET_STAGE1 \
     --target=$TARGET_STAGE1
 
 build-commands:
-# Nested configure scripts require that we set CPPFLAGS here as well
-# (I don't think we should have to .. . at least in GCC, I think
-# TARGET_CPPFLAGS may be the answer)
 - |
   export STAGE2_SYSROOT="$(dirname $(pwd))"
-  export CPPFLAGS="--sysroot=$STAGE2_SYSROOT"
-  export LDFLAGS="-Wl,--sysroot=$STAGE2_SYSROOT"
   make