scripts: check host features with host compiler

Currently, we check host feature in ./configure. This works only for
cross toolchains, but not for canadian toolchains. ./configure has
absolutely no way to know what the host for the toolchain will be;
only the build scripts know.

So, move the headers & libraries checks from ./configure to the build
scripts, early enough in the build, but not before we know the host
compiler and other tools.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

config/cc/gcc.in.2

@@ -44,9 +44,8 @@ config CC_STATIC_LIBSTDCXX
     bool
     prompt "Link libstdc++ statically into the gcc binary"
     default y
-    depends on CONFIGURE_static_link_ok
-    depends on CONFIGURE_has_static_libstdcxx
     depends on CC_GCC_4_4_or_later
+    select WANTS_STATIC_LINK
     help
       Newer gcc versions use the PPL library which is C++ code.  Statically
       linking libstdc++ increases the likeliness that the gcc binary will

config/debug/gdb.in.cross

@@ -3,18 +3,10 @@
 config STATIC_TOOLCHAIN
     select GDB_CROSS_STATIC if GDB_CROSS
 
-comment "Cross-gdb - disabled (requires expat; re-run ./configure to enable)"
-    depends on !CONFIGURE_has_expat
-
-comment "Static cross-gdb - disabled (requires static expat; re-run ./configure to enable)"
-    depends on STATIC_TOOLCHAIN && !CONFIGURE_has_static_expat
-
 config GDB_CROSS
     bool
     prompt "Cross-gdb"
     default y
-    depends on CONFIGURE_has_expat
-    depends on !STATIC_TOOLCHAIN || CONFIGURE_has_static_expat
     select GDB_GDBSERVER if ! BARE_METAL
     help
       Build and install a cross-gdb for the target, to run on host.
@@ -24,8 +16,7 @@ if GDB_CROSS
 config GDB_CROSS_STATIC
     bool
     prompt "Build a static cross gdb"
-    depends on CONFIGURE_static_link_ok
+    select WANTS_STATIC_LINK
-    depends on CONFIGURE_has_static_expat
     help
       A static cross gdb can be usefull if you debug on a machine that is
       not the one that is used to compile the toolchain.
@@ -36,7 +27,6 @@ config GDB_CROSS_STATIC
 config GDB_CROSS_PYTHON
     bool
     prompt "Enable python scripting"
-    depends on CONFIGURE_has_python
     depends on ! GDB_CROSS_STATIC
     default y
     help

config/debug/gdb.in.native

@@ -10,13 +10,9 @@ config GDB_NATIVE
 
 if GDB_NATIVE
 
-config GDB_NATIVE_NO_STATIC
-    bool
-
 config GDB_NATIVE_STATIC
     bool
     prompt "Build a static native gdb"
-    depends on ! GDB_NATIVE_NO_STATIC
     help
       In case you have trouble with dynamic loading of shared libraries,
       you will find that a static gdb comes in handy.

config/toolchain.in

@@ -46,20 +46,14 @@ config SYSROOT_DIR_PREFIX
       In fact, the sysroot path is constructed as:
         ${CT_PREFIX_DIR}/${CT_TARGET}/${CT_SYSROOT_DIR_PREFIX}/${CT_SYSROOT_NAME}
 
-# In case we need to add more conditions to enable static
+config WANTS_STATIC_LINK
-# toolchain, we'll be adding them here
-config STATIC_TOOLCHAIN_POSSIBLE
     bool
-    default y
-    depends on CONFIGURE_static_link_ok
-    depends on CONFIGURE_has_static_libstdcxx
-    # Add new deps here! :-)
 
 config STATIC_TOOLCHAIN
     bool
     prompt "Build Static Toolchain (EXPERIMENTAL)"
     depends on EXPERIMENTAL
-    depends on STATIC_TOOLCHAIN_POSSIBLE
+    select WANTS_STATIC_LINK
     help
       Build static host binaries.
       
@@ -68,8 +62,9 @@ config STATIC_TOOLCHAIN
       you can say 'Y' here, and all the host tools will be linked statically.
       
       The impacted tools are:
-        - the GNU binutils
+        - the cross-binutils (GNU binutils, elf2flt)
-        - the cross-gdb
+        - the cross-compiler (gcc)
+        - the cross-debugger (gdb)
       
       The default is 'N', to build dynamicaly-linked host binaries.
       

configure

@@ -534,36 +534,8 @@ case "${host}" in
         ;;
 esac
 
-printf "Checking if static linking is possible... "
-static_link_ok=""
-case "${host}" in
-    Darwin) ;;
-    *)  tmp=.static.tmp
-        if gcc -xc - -static -o "${tmp}" >/dev/null 2>&1 <<-_EOF_
-				int main() { return 0; }
-			_EOF_
-        then
-            static_link_ok="y"
-        fi
-        rm -f "${tmp}"
-        ;;
-esac
-if [ "${static_link_ok}" = "y" ]; then
-    static_link_ko=""
-    printf "yes\n"
-else
-    static_link_ko="y"
-    printf "no\n"
-    printf " * An optional host feature is missing, some features will be disabled:\n"
-    printf " * - It will not be possible to statically link toolchain's binaries\n"
-fi
-add_to_kconfig_list static_link_ok
-
 # Library checks
-libs_exts="so dylib"
+libs_exts="so dylib a"
-if [ "${static_link_ok}" = "y" ]; then
-    libs_exts="${libs_exts} a"
-fi
 
 ncurses_hdrs="ncurses/ncurses.h ncurses/curses.h ncurses.h curses.h"
 ncurses_libs="libncursesw libncurses libcurses"
@@ -572,46 +544,6 @@ has_or_abort lib="${ncurses_libs}"                                          \
              inc="${ncurses_hdrs}"                                          \
              err="The 'ncurses' library is needed fo the menuconfig frontend"
 
-has_or_abort lib="libstdc++"            \
-             lib_exts="${libs_exts}"    \
-             err="The 'libstdc++' library is needed to build gcc"
-
-# Yes, we may be checking twice for libstdc++.a
-# The first is because we need one instance of libstdc++ (shared or static)
-# because it is needed for PPL; the second is because the static version is
-# required for static-linking, and if missing, the option is removed.
-has_or_warn  lib="libstdc++"                \
-             lib_exts="a"                   \
-             err="static 'libstdc++' is needed to statically link the toolchain's executables" \
-             kconfig=has_static_libstdcxx   \
-             skip="${static_link_ko}"
-
-has_or_warn  inc="expat.h"              \
-             lib="libexpat"             \
-             lib_exts="${libs_exts}"    \
-             err="The 'expat' header file and library are needed to link cross-gdb's executables" \
-             kconfig=has_expat
-
-# Yes, we may be checking twice for libexpat.a
-# The first is because we need one instance of libexpat (shared or static)
-# because it is needed for cross-gdb; the second is because the static version
-# is required for static-linking, and if missing, the option is removed.
-has_or_warn  lib="libexpat"             \
-             lib_exts="a"               \
-             err="static 'expat' is needed to statically link cross-gdb's executables" \
-             kconfig=has_static_expat   \
-             skip="${static_link_ko}"
-
-for v in 7 6 5 4; do
-    python_incs="${python_incs} python2.${v}/Python.h"
-    python_libs="${python_libs} libpython2.${v}"
-done
-has_or_warn  inc="${python_incs}"       \
-             lib="${python_libs}"       \
-             lib_exts="${libs_exts}"    \
-             kconfig=has_python         \
-             err="The 'python' header file and library are needed for some features of cross-gdb"
-
 #---------------------------------------------------------------------
 # Compute the version string
 

scripts/crosstool-NG.sh.in

@@ -464,6 +464,19 @@ if [ -z "${CT_RESTART}" ]; then
         *)  ;;
     esac
 
+    # Now we know our host and where to find the host tools, we can check
+    # if static link was requested, but only if it was requested
+    if [ "${CT_WANTS_STATIC_LINK}" = "y" ]; then
+        tmp="${CT_BUILD_DIR}/.static-test"
+        if ! "${CT_HOST}-gcc" -xc - -static -o "${tmp}" >/dev/null 2>&1 <<-_EOF_
+				int main() { return 0; }
+			_EOF_
+        then
+            CT_Abort "Static linking impossible on the host system '${CT_HOST}'"
+        fi
+        rm -f "${tmp}"
+    fi
+
     # Help gcc
     CT_CFLAGS_FOR_HOST=
     [ "${CT_USE_PIPES}" = "y" ] && CT_CFLAGS_FOR_HOST+=" -pipe"