Enable building expat/ncurses for host.

Then re-enable cross-gdb for nios2-spico-elf sample, previously
disabled.

config/debug/gdb.in.cross

@@ -8,6 +8,8 @@ config GDB_CROSS
     prompt "Cross-gdb"
     default y
     select GDB_GDBSERVER if ! BARE_METAL
+    select EXPAT_NEEDED
+    select NCURSES_NEEDED
     help
       Build and install a cross-gdb for the target, to run on host.
 

samples/i686-w64-mingw32,nios2-spico-elf/crosstool.config

@@ -12,7 +12,6 @@ CT_HOST="i686-w64-mingw32"
 CT_BINUTILS_V_2_25=y
 CT_CC_LANG_CXX=y
 CT_DEBUG_gdb=y
-# CT_GDB_CROSS is not set
 CT_MPFR_V_3_1_2=y
 CT_ISL_V_0_12_2=y
 CT_MPC_V_1_0_2=y

scripts/build/companion_libs/210-expat.sh

@@ -18,6 +18,21 @@ do_expat_extract() {
     CT_Patch "expat" "${CT_EXPAT_VERSION}"
 }
 
+if [ "${CT_EXPAT}" = "y" ]; then
+# Do not need expat for build at this time.
+
+do_expat_for_host() {
+    CT_DoStep INFO "Installing expat for host"
+    CT_mkdir_pushd "${CT_BUILD_DIR}/build-expat-host-${CT_HOST}"
+
+    do_expat_backend host="${CT_HOST}" \
+                     prefix="${CT_HOST_COMPLIBS_DIR}"
+
+    CT_Popd
+    CT_EndStep
+}
+fi
+
 if [ "${CT_EXPAT_TARGET}" = "y" ]; then
 do_expat_for_target() {
     CT_DoStep INFO "Installing expat for target"

scripts/build/companion_libs/220-ncurses.sh

@@ -23,6 +23,7 @@ do_ncurses_extract() {
 # We need tic that runs on the build when building ncurses for host/target
 do_ncurses_for_build() {
     local -a opts
+
     CT_DoStep INFO "Installing ncurses for build"
     CT_mkdir_pushd "${CT_BUILD_DIR}/build-ncurses-build-${CT_BUILD}"
     opts=("--enable-symlinks" \
@@ -38,6 +39,33 @@ do_ncurses_for_build() {
     CT_EndStep
 }
 
+if [ "${CT_NCURSES}" = "y" ]; then
+do_ncurses_for_host() {
+    local -a opts
+
+    # Unlike other companion libs, we skip host build if build==host
+    # (i.e. in simple cross or native): ncurses may not be needed for
+    # host, but we still need them on build to produce 'tic'.
+    case "${CT_TOOLCHAIN_TYPE}" in
+        native|cross)   return 0;;
+    esac
+
+    CT_DoStep INFO "Installing ncurses for host"
+    CT_mkdir_pushd "${CT_BUILD_DIR}/build-ncurses-host-${CT_HOST}"
+    opts=("--enable-symlinks" \
+          "--without-manpages" \
+          "--without-tests" \
+          "--without-cxx" \
+          "--without-cxx-binding" \
+          "--without-ada")
+    do_ncurses_backend host="${CT_HOST}" \
+                       prefix="${CT_HOST_COMPLIBS_DIR}" \
+                       "${opts[@]}"
+    CT_Popd
+    CT_EndStep
+}
+fi
+
 if [ "${CT_NCURSES_TARGET}" = "y" ]; then
 do_ncurses_for_target() {
     CT_DoStep INFO "Installing ncurses for target"
@@ -81,6 +109,15 @@ do_ncurses_backend() {
         esac
     done
 
+    case "$host" in
+        *-*-mingw*)
+            # Needed to build for mingw, see
+            # http://lists.gnu.org/archive/html/info-gnu/2011-02/msg00020.html
+            ncurses_opts+=("--enable-term-driver")
+            ncurses_opts+=("--enable-sp-funcs")
+            ;;
+    esac
+
     CT_DoLog EXTRA "Configuring ncurses"
     CT_DoExecLog CFG                                                    \
     "${CT_SRC_DIR}/ncurses-${CT_NCURSES_VERSION}/configure"             \

scripts/build/debug/300-gdb.sh

@@ -96,8 +96,8 @@ do_debug_gdb_build() {
         cd "${CT_BUILD_DIR}/build-gdb-cross"
 
         cross_extra_config=("${extra_config[@]}")
-        cross_extra_config+=("--enable-expat")
-        cross_extra_config+=("--with-expat=yes")
+        cross_extra_config+=("--with-expat")
+        cross_extra_config+=("--with-libexpat-prefix=${CT_HOST_COMPLIBS_DIR}")
         case "${CT_THREADS}" in
             none)   cross_extra_config+=("--disable-threads");;
             *)      cross_extra_config+=("--enable-threads");;