Add moxiebox as a choice for libc

This required some rework of the libc selection, as moxiebox is a layer on
top of another libc - newlib.

Also, moxiebox'es host VM (`sandbox`) needs a libcrypto on the host. We will
not have it if we're cross-compiling a canadian cross. Fortunately, all moxiebox
needs from libcrypto is SHA256, and it already includes a standalone implementation
of SHA256 in its runtime. Provide a little wrapper that allows moxiebox use
that implementation for the host binary, too.

Also, automate collecting/printing the list of all packages in a given category
(e.g. LIBC or COMP_TOOLS), generate a list of all Kconfig symbols for a given
category.

Signed-off-by: Alexey Neyman <stilor@att.net>

15 files changed, 238 insertions, 185 deletions

diff --git a/scripts/build/arch/avr.sh b/scripts/build/arch/avr.sh
index 501b020..fd8c8ed 100644
--- a/scripts/build/arch/avr.sh
+++ b/scripts/build/arch/avr.sh
@@ -2,4 +2,11 @@
 
 CT_DoArchTupleValues() {
     CT_TARGET_ARCH="${CT_ARCH}"
+    case "${CT_LIBC}" in
+    avr-libc)
+        # avr-libc only seems to work with the non-canonical "avr" target.
+        CT_TARGET_SKIP_CONFIG_SUB=y
+        CT_TARGET_SYS= # CT_TARGET_SYS must be empty
+        ;;
+    esac
 }
diff --git a/scripts/build/arch/moxie.sh b/scripts/build/arch/moxie.sh
index 91a9969..72c82c9 100644
--- a/scripts/build/arch/moxie.sh
+++ b/scripts/build/arch/moxie.sh
@@ -3,5 +3,9 @@
 # No arch-specific overrides yet
 CT_DoArchTupleValues()
 {
-    :
+    case "${CT_LIBC}" in
+    moxiebox)
+        CT_TARGET_SYS=moxiebox
+        ;;
+    esac
 }
diff --git a/scripts/build/libc.sh b/scripts/build/libc.sh
new file mode 100644
index 0000000..fb1ebe5
--- /dev/null
+++ b/scripts/build/libc.sh
@@ -0,0 +1,39 @@
+# C library build routines. We don't invoke the corresponding functions directly
+# because some of them build on top of another. E.g. moxiebox runtime requires
+# newlib as a prerequisite.
+
+# Define default hooks - download/unpack just the main package; no-op build hooks.
+# The actual implementation can override just what it needs then.
+eval "${CT_LIBC//[^A-Za-z0-9]/_}_get() { CT_Fetch ${CT_LIBC_CHOICE_KSYM}; }"
+eval "${CT_LIBC//[^A-Za-z0-9]/_}_extract() { CT_ExtractPatch ${CT_LIBC_CHOICE_KSYM}; }"
+for _m in start_files main post_cc; do
+    eval "${CT_LIBC//[^A-Za-z0-9]/_}_${_m}() { :; }"
+done
+
+# Source the selected libc.
+. "${CT_LIB_DIR}/scripts/build/libc/${CT_LIBC}.sh"
+
+do_libc_get()
+{
+    eval "${CT_LIBC//[^A-Za-z0-9]/_}_get"
+}
+
+do_libc_extract()
+{
+    eval "${CT_LIBC//[^A-Za-z0-9]/_}_extract"
+}
+
+do_libc_start_files()
+{
+    eval "${CT_LIBC//[^A-Za-z0-9]/_}_start_files"
+}
+
+do_libc_main()
+{
+    eval "${CT_LIBC//[^A-Za-z0-9]/_}_main"
+}
+
+do_libc_post_cc()
+{
+    eval "${CT_LIBC//[^A-Za-z0-9]/_}_post_cc"
+}
diff --git a/scripts/build/libc/avr-libc.sh b/scripts/build/libc/avr-libc.sh
index 7003f38..ce63b4a 100644
--- a/scripts/build/libc/avr-libc.sh
+++ b/scripts/build/libc/avr-libc.sh
@@ -1,22 +1,7 @@
 # This file adds functions to build the avr-libc C library
 
-do_libc_get() {
-    CT_Fetch AVR_LIBC
-}
-
-do_libc_extract() {
-    CT_ExtractPatch AVR_LIBC
-}
-
-do_libc_start_files() {
-    :
-}
-
-do_libc() {
-    :
-}
-
-do_libc_post_cc() {
+avr_libc_post_cc()
+{
     CT_DoStep INFO "Installing C library"
 
     CT_DoLog EXTRA "Copying sources to build directory"
diff --git a/scripts/build/libc/bionic.sh b/scripts/build/libc/bionic.sh
index 93dcea0..9f04e61 100644
--- a/scripts/build/libc/bionic.sh
+++ b/scripts/build/libc/bionic.sh
@@ -2,21 +2,15 @@
 # Copyright 2017 Howard Chu
 # Licensed under the GPL v2. See COPYING in the root of this package
 
-do_libc_get() {
-    CT_Fetch ANDROID_NDK
-}
-
-do_libc_extract() {
-    CT_ExtractPatch ANDROID_NDK
-}
-
 # Install Unified headers
-do_libc_start_files() {
+bionic_start_files()
+{
     CT_DoStep INFO "Installing C library headers"
     CT_DoExecLog ALL cp -r "${CT_SRC_DIR}/android-ndk/sysroot/usr" "${CT_SYSROOT_DIR}"
 }
 
-do_libc() {
+bionic_main()
+{
     local arch="${CT_ARCH}"
     if [ "${CT_ARCH_64}" = "y" ]; then
         if [ "${CT_ARCH}" = "x86" ]; then
@@ -34,8 +28,3 @@ do_libc() {
     # options isn't completely out of character.
     CT_EnvModify CT_TARGET_CFLAGS "${CT_TARGET_CFLAGS} -D__ANDROID_API__=${CT_ANDROID_API}"
 }
-
-do_libc_post_cc() {
-    :
-}
-
diff --git a/scripts/build/libc/glibc.sh b/scripts/build/libc/glibc.sh
index 125ccf7..a9adbbb 100644
--- a/scripts/build/libc/glibc.sh
+++ b/scripts/build/libc/glibc.sh
@@ -2,7 +2,8 @@
 # Copyright 2007 Yann E. MORIN
 # Licensed under the GPL v2. See COPYING in the root of this package
 
-do_libc_get() {
+glibc_get()
+{
     local date
     local version
 
@@ -13,7 +14,8 @@ do_libc_get() {
     return 0
 }
 
-do_libc_extract() {
+glibc_extract()
+{
     CT_ExtractPatch GLIBC
     if [ "${CT_GLIBC_USE_PORTS_EXTERNAL}" = "y" ]; then
         CT_ExtractPatch GLIBC_PORTS
@@ -29,27 +31,26 @@ do_libc_extract() {
 }
 
 # Build and install headers and start files
-do_libc_start_files() {
+glibc_start_files()
+{
     # Start files and Headers should be configured the same way as the
     # final libc, but built and installed differently.
-    do_libc_backend libc_mode=startfiles
+    glibc_backend libc_mode=startfiles
 }
 
 # This function builds and install the full C library
-do_libc() {
-    do_libc_backend libc_mode=final
-}
-
-do_libc_post_cc() {
-    :
+glibc_main()
+{
+    glibc_backend libc_mode=final
 }
 
 # This backend builds the C library once for each multilib
 # variant the compiler gives us
-# Usage: do_libc_backend param=value [...]
+# Usage: glibc_backend param=value [...]
 #   Parameter           : Definition                            : Type      : Default
 #   libc_mode           : 'startfiles' or 'final'               : string    : (none)
-do_libc_backend() {
+glibc_backend()
+{
     local libc_mode
     local arg
 
@@ -70,17 +71,18 @@ do_libc_backend() {
     esac
 
     CT_mkdir_pushd "${CT_BUILD_DIR}/build-libc-${libc_mode}"
-    CT_IterateMultilibs do_libc_backend_once multilib libc_mode="${libc_mode}"
+    CT_IterateMultilibs glibc_backend_once multilib libc_mode="${libc_mode}"
     CT_Popd
     CT_EndStep
 }
 
 # This backend builds the C library once
-# Usage: do_libc_backend_once param=value [...]
+# Usage: glibc_backend_once param=value [...]
 #   Parameter           : Definition                            : Type
 #   libc_mode           : 'startfiles' or 'final'               : string    : (empty)
 #   multi_*             : as defined in CT_IterateMultilibs     : (varies)  :
-do_libc_backend_once() {
+glibc_backend_once()
+{
     local multi_flags multi_dir multi_os_dir multi_root multi_index multi_count multi_target
     local build_cflags build_cppflags build_ldflags
     local startfiles_dir
@@ -136,7 +138,7 @@ do_libc_backend_once() {
     # values, as they CT_GLIBC_EXTRA_CONFIG_ARRAY is passed after
     # extra_config
 
-    extra_config+=("$(do_libc_min_kernel_config)")
+    extra_config+=("$(glibc_min_kernel_config)")
 
     case "${CT_THREADS}" in
         nptl)           extra_config+=("--with-__thread" "--with-tls");;
@@ -165,9 +167,9 @@ do_libc_backend_once() {
         extra_config+=("--enable-oldest-abi=${CT_GLIBC_OLDEST_ABI}")
     fi
 
-    case "$(do_libc_add_ons_list ,)" in
+    case "$(glibc_add_ons_list ,)" in
         "") extra_config+=("--enable-add-ons=no");;
-        *)  extra_config+=("--enable-add-ons=$(do_libc_add_ons_list ,)");;
+        *)  extra_config+=("--enable-add-ons=$(glibc_add_ons_list ,)");;
     esac
 
     [ "${CT_GLIBC_ENABLE_WERROR}" != "y" ] && extra_config+=("--disable-werror")
@@ -241,7 +243,7 @@ do_libc_backend_once() {
     # Run explicitly through CONFIG_SHELL, or the build breaks badly (loop-of-death)
     # when the shell is not bash... Sigh... :-(
 
-    CT_DoLog DEBUG "Configuring with addons  : '$(do_libc_add_ons_list ,)'"
+    CT_DoLog DEBUG "Configuring with addons  : '$(glibc_add_ons_list ,)'"
     CT_DoLog DEBUG "Extra config args passed : '${extra_config[*]}'"
     CT_DoLog DEBUG "Extra CFLAGS passed      : '${glibc_cflags}'"
     CT_DoLog DEBUG "Placing startfiles into  : '${startfiles_dir}'"
@@ -402,7 +404,7 @@ do_libc_backend_once() {
         fi
 
         if [ "${CT_GLIBC_LOCALES}" = "y" -a "${multi_index}" = "${multi_count}" ]; then
-            do_libc_locales
+            glibc_locales
         fi
     fi # libc_mode = final
 
@@ -410,7 +412,8 @@ do_libc_backend_once() {
 }
 
 # Build up the addons list, separated with $1
-do_libc_add_ons_list() {
+glibc_add_ons_list()
+{
     local sep="$1"
     local addons_list
 
@@ -427,7 +430,8 @@ do_libc_add_ons_list() {
 }
 
 # Compute up the minimum supported Linux kernel version
-do_libc_min_kernel_config() {
+glibc_min_kernel_config()
+{
     local min_kernel_config
 
     case "${CT_GLIBC_EXTRA_CONFIG_ARRAY[*]}" in
@@ -462,7 +466,8 @@ do_libc_min_kernel_config() {
 }
 
 # Build and install the libc locales
-do_libc_locales() {
+glibc_locales()
+{
     local src_dir="${CT_SRC_DIR}/glibc"
     local -a extra_config
     local glibc_cflags
diff --git a/scripts/build/libc/mingw-w64.sh b/scripts/build/libc/mingw-w64.sh
index 3026b87..6e87073 100644
--- a/scripts/build/libc/mingw-w64.sh
+++ b/scripts/build/libc/mingw-w64.sh
@@ -1,22 +1,15 @@
 # Copyright 2012 Yann Diorcet
 # Licensed under the GPL v2. See COPYING in the root of this package
 
-do_libc_get() {
-    CT_Fetch MINGW_W64
-}
-
-do_libc_extract() {
-    CT_ExtractPatch MINGW_W64
-}
-
-do_set_mingw_install_prefix(){
+mingw_w64_set_install_prefix()
+{
     MINGW_INSTALL_PREFIX=/usr/${CT_TARGET}
     if [[ ${CT_MINGW_W64_VERSION} == 2* ]]; then
         MINGW_INSTALL_PREFIX=/usr
     fi
 }
 
-do_libc_start_files() {
+mingw_w64_start_files() {
     local -a sdk_opts
 
     CT_DoStep INFO "Installing C library headers"
@@ -36,7 +29,7 @@ do_libc_start_files() {
 
     CT_DoLog EXTRA "Configuring Headers"
 
-    do_set_mingw_install_prefix
+    mingw_w64_set_install_prefix
     CT_DoExecLog CFG        \
     ${CONFIG_SHELL} \
     "${CT_SRC_DIR}/mingw-w64/mingw-w64-headers/configure" \
@@ -96,7 +89,7 @@ do_mingw_tools()
             --program-prefix=${CT_TARGET}- \
             --prefix="${CT_PREFIX_DIR}"
 
-        # mingw-w64 has issues with parallel builds, see do_libc
+        # mingw-w64 has issues with parallel builds, see mingw_w64_main
         CT_DoLog EXTRA "Building ${f}"
         CT_DoExecLog ALL make
         CT_DoLog EXTRA "Installing ${f}"
@@ -154,7 +147,7 @@ do_mingw_pthreads()
         --build=${CT_BUILD} \
         --host=${multi_target}
 
-    # mingw-w64 has issues with parallel builds, see do_libc
+    # mingw-w64 has issues with parallel builds, see mingw_w64_main
     CT_DoLog EXTRA "Building mingw-w64-winpthreads"
     CT_DoExecLog ALL make
 
@@ -179,7 +172,7 @@ do_mingw_pthreads()
     CT_EndStep
 }
 
-do_libc()
+mingw_w64_main()
 {
     # Used when iterating over libwinpthread
     local default_libprefix
@@ -192,7 +185,7 @@ do_libc()
 
     CT_mkdir_pushd "${CT_BUILD_DIR}/build-mingw-w64-crt"
 
-    do_set_mingw_install_prefix
+    mingw_w64_set_install_prefix
     CT_DoExecLog CFG \
     ${CONFIG_SHELL} \
     "${CT_SRC_DIR}/mingw-w64/mingw-w64-crt/configure" \
@@ -228,6 +221,6 @@ do_libc()
     fi
 }
 
-do_libc_post_cc() {
+mingw_w64_post_cc() {
     :
 }
diff --git a/scripts/build/libc/moxiebox.sh b/scripts/build/libc/moxiebox.sh
new file mode 100644
index 0000000..376c742
--- /dev/null
+++ b/scripts/build/libc/moxiebox.sh
@@ -0,0 +1,84 @@
+# Functions to build the moxiebox runtime.
+
+. "${CT_LIB_DIR}/scripts/build/libc/newlib.sh"
+
+moxiebox_get()
+{
+    CT_Fetch NEWLIB
+    CT_Fetch MOXIEBOX
+}
+
+moxiebox_extract()
+{
+    CT_ExtractPatch NEWLIB
+    CT_ExtractPatch MOXIEBOX
+}
+
+moxiebox_start_files()
+{
+    newlib_start_files
+}
+
+moxiebox_main()
+{
+    newlib_main
+
+    # newlib installs the linker script, moxiebox.ld, to the
+    # PREFIX/moxie-unknown-moxiebox/lib, but ld searches PREFIX/lib when
+    # configured for that target. ld does find scripts in PREFIX/TARGET/lib
+    # for other targets, so this seems to be moxie architecture's quirk.
+    # Move it to PREFIX/lib.
+    # TBD CT_DoExecLog ALL mv -v "${CT_SYSROOT_DIR}/lib/"*.ld "${CT_PREFIX_DIR}/lib"
+    # TBD what about moxie-*-elf? Does it need the same?
+
+    CT_DoStep INFO "Installing moxiebox runtime and VM"
+
+    CT_mkdir_pushd "${CT_BUILD_DIR}/build-libc-moxiebox"
+    CT_DoExecLog ALL cp -av "${CT_SRC_DIR}/moxiebox/." .
+
+    CT_DoLog EXTRA "Building SHA256-only libcrypto"
+    # Moxiebox needs libcrypto on the host, but it only uses SHA256 digest functions
+    # from it. We don't want to pull the whole OpenSSL for the host; fortunately,
+    # moxiebox comes with a standalone SHA256 implementation - which it only uses
+    # for the target library. Help it use the same implementation for the host.
+    CT_mkdir_pushd openssl
+    CT_DoExecLog ALL cp -v "${CT_LIB_DIR}/packages/moxiebox/"sha*.[ch] ./
+    CT_DoExecLog ALL "${CT_HOST}-gcc" -c sha256_wrap.c -O2 -Wall
+    CT_DoExecLog ALL "${CT_HOST}-ar" cru libcrypto.a sha256_wrap.o
+    CT_Popd 
+
+    # Moxiebox includes a VM which we're building for the
+    # host machine.
+    CT_DoLog EXTRA "Configuring moxiebox"
+
+    CT_DoExecLog CFG ./autogen.sh
+
+    # moxiebox build script create symlinks from the installation location to the build
+    # directory for the moxiebox library. This seems backwards. Instead, pass the search
+    # as part of the MOX_GCC definition.
+    # moxiebox also depends on the tools being named moxiebox-{gcc,as,ar}. However, failure
+    # to detect such tools is non-fatal in the configure and we need to override it in
+    # make's command line anyway.
+    CT_DoExecLog CFG \
+            LDFLAGS="${CT_LDFLAGS_FOR_HOST} -L${CT_BUILD_DIR}/build-libc-moxiebox/openssl" \
+            CFLAGS="${CT_CFLAGS_FOR_HOST} -I${CT_BUILD_DIR}/build-libc-moxiebox" \
+            CXXFLAGS="${CT_CFLAGS_FOR_HOST} -I${CT_BUILD_DIR}/build-libc-moxiebox" \
+            ./configure \
+            --host="${CT_HOST}"
+    CT_DoLog EXTRA "Building moxiebox"
+    CT_DoExecLog CFG make all \
+            MOX_GCC="${CT_TARGET}-gcc -B ${CT_BUILD_DIR}/build-libc-moxiebox/runtime -B ${CT_SYSROOT_DIR}/lib" \
+            MOX_AS="${CT_TARGET}-as" \
+            MOX_AR="${CT_TARGET}-ar"
+
+    CT_DoLog EXTRA "Installing moxiebox"
+
+    # moxiebox does not have install target. Copy the interesting stuff manually.
+    CT_DoExecLog ALL cp -v "${CT_BUILD_DIR}/build-libc-moxiebox/runtime/libsandboxrt.a" \
+            "${CT_BUILD_DIR}/build-libc-moxiebox/runtime/crt0.o" \
+            "${CT_SYSROOT_DIR}/lib/"
+    CT_DoExecLog ALL cp -v "${CT_BUILD_DIR}/build-libc-moxiebox/src/sandbox" \
+            "${CT_PREFIX_DIR}/bin"
+    CT_Popd
+    CT_EndStep
+}
diff --git a/scripts/build/libc/musl.sh b/scripts/build/libc/musl.sh
index 430fb8d..0a93d10 100644
--- a/scripts/build/libc/musl.sh
+++ b/scripts/build/libc/musl.sh
@@ -2,33 +2,27 @@
 # Copyright 2013 Timo Teräs
 # Licensed under the GPL v2. See COPYING in the root of this package
 
-do_libc_get() {
-    CT_Fetch MUSL
-}
-
-do_libc_extract() {
-    CT_ExtractPatch MUSL
-}
-
 # Build and install headers and start files
-do_libc_start_files() {
+musl_start_files()
+{
     # Start files and Headers should be configured the same way as the
     # final libc, but built and installed differently.
-    do_libc_backend libc_mode=startfiles
+    musl_backend libc_mode=startfiles
 }
 
 # This function builds and install the full C library
-do_libc() {
-    do_libc_backend libc_mode=final
+musl_main()
+{
+    musl_backend libc_mode=final
 }
 
-do_libc_post_cc() {
+musl_post_cc() {
     # MUSL creates dynamic linker symlink with absolute path - which works on the
     # target but not on the host. We want our cross-ldd tool to work.
     CT_MultilibFixupLDSO
 }
 
-do_libc_backend() {
+musl_backend() {
     local libc_mode
     local arg
 
@@ -43,16 +37,16 @@ do_libc_backend() {
     esac
 
     CT_mkdir_pushd "${CT_BUILD_DIR}/build-libc-${libc_mode}"
-    CT_IterateMultilibs do_libc_backend_once multilib libc_mode="${libc_mode}"
+    CT_IterateMultilibs musl_backend_once multilib libc_mode="${libc_mode}"
     CT_Popd
     CT_EndStep
 }
 
 # This backend builds the C library
-# Usage: do_libc_backend param=value [...]
+# Usage: musl_backend param=value [...]
 #   Parameter           : Definition                      : Type      : Default
 #   libc_mode           : 'startfiles' or 'final'         : string    : (none)
-do_libc_backend_once() {
+musl_backend_once() {
     local libc_mode
     local -a extra_cflags
     local -a extra_config
diff --git a/scripts/build/libc/newlib.sh b/scripts/build/libc/newlib.sh
index 6449d68..69d2b46 100644
--- a/scripts/build/libc/newlib.sh
+++ b/scripts/build/libc/newlib.sh
@@ -5,15 +5,8 @@
 # Edited by Martin Lund <mgl@doredevelopment.dk>
 #
 
-do_libc_get() {
-    CT_Fetch NEWLIB
-}
-
-do_libc_extract() {
-    CT_ExtractPatch NEWLIB
-}
-
-do_libc_start_files() {
+newlib_start_files()
+{
     CT_DoStep INFO "Installing C library headers & start files"
     CT_DoExecLog ALL cp -a "${CT_SRC_DIR}/newlib/newlib/libc/include/." \
     "${CT_HEADERS_DIR}"
@@ -25,14 +18,14 @@ do_libc_start_files() {
     CT_EndStep
 }
 
-do_libc() {
+newlib_main()
+{
     local -a newlib_opts
     local cflags_for_target
 
     CT_DoStep INFO "Installing C library"
 
-    mkdir -p "${CT_BUILD_DIR}/build-libc"
-    cd "${CT_BUILD_DIR}/build-libc"
+    CT_mkdir_pushd "${CT_BUILD_DIR}/build-libc"
 
     CT_DoLog EXTRA "Configuring C library"
 
@@ -135,9 +128,6 @@ ENABLE_TARGET_OPTSPACE:target-optspace
                                 "${CT_PREFIX_DIR}/share/doc/newlib"
     fi
 
+    CT_Popd
     CT_EndStep
 }
-
-do_libc_post_cc() {
-    :
-}
diff --git a/scripts/build/libc/none.sh b/scripts/build/libc/none.sh
index 8537a8e..5173afb 100644
--- a/scripts/build/libc/none.sh
+++ b/scripts/build/libc/none.sh
@@ -2,22 +2,12 @@
 # Copyright 2008 Yann E. MORIN
 # Licensed under the GPL v2. See COPYING in the root of this package
 
-do_libc_get() {
+none_get()
+{
     :
 }
 
-do_libc_extract() {
-    :
-}
-
-do_libc_start_files() {
-    :
-}
-
-do_libc() {
-    :
-}
-
-do_libc_post_cc() {
+none_extract()
+{
     :
 }
diff --git a/scripts/build/libc/uClibc.sh b/scripts/build/libc/uClibc.sh
index eb6cf5b..ed2ea90 100644
--- a/scripts/build/libc/uClibc.sh
+++ b/scripts/build/libc/uClibc.sh
@@ -2,30 +2,23 @@
 # Copyright 2007 Yann E. MORIN
 # Licensed under the GPL v2. See COPYING in the root of this package
 
-# Download uClibc
-do_libc_get() {
-    CT_Fetch UCLIBC
-}
-
-# Extract uClibc
-do_libc_extract() {
-    CT_ExtractPatch UCLIBC
-}
-
 # Build and install headers and start files
-do_libc_start_files() {
+uclibc_start_files()
+{
     # Start files and Headers should be configured the same way as the
     # final libc, but built and installed differently.
-    do_libc_backend libc_mode=startfiles
+    uclibc_backend libc_mode=startfiles
 }
 
 # This function builds and install the full C library
-do_libc() {
-    do_libc_backend libc_mode=final
+uclibc_main()
+{
+    uclibc_backend libc_mode=final
 }
 
 # Common backend for 1st and 2nd passes.
-do_libc_backend() {
+uclibc_backend()
+{
     local libc_mode
     local arg
 
@@ -40,13 +33,14 @@ do_libc_backend() {
     esac
 
     CT_mkdir_pushd "${CT_BUILD_DIR}/build-libc-${libc_mode}"
-    CT_IterateMultilibs do_libc_backend_once multilib libc_mode="${libc_mode}"
+    CT_IterateMultilibs uclibc_backend_once multilib libc_mode="${libc_mode}"
     CT_Popd
     CT_EndStep
 }
 
 # Common backend for 1st and 2nd passes, once per multilib.
-do_libc_backend_once() {
+uclibc_backend_once()
+{
     local libc_mode
     local multi_dir multi_os_dir multi_root multi_flags multi_index multi_count
     local multilib_dir startfiles_dir
@@ -215,7 +209,8 @@ do_libc_backend_once() {
 # Initialises the .config file to sensible values
 # $1: original file
 # $2: modified file
-manage_uClibc_config() {
+manage_uClibc_config()
+{
     src="$1"
     dst="$2"
     flags="$3"
@@ -408,7 +403,8 @@ manage_uClibc_config() {
     CT_DoArchUClibcCflags "${dst}" "${flags}"
 }
 
-do_libc_post_cc() {
+uclibc_post_cc()
+{
     # uClibc and GCC disagree where the dynamic linker lives. uClibc always
     # places it in the MULTILIB_DIR, while gcc does that for *some* variants
     # and expects it in /lib for the other. So, create a symlink from lib
diff --git a/scripts/crosstool-NG.sh b/scripts/crosstool-NG.sh
index ccfe29c..b60976c 100644
--- a/scripts/crosstool-NG.sh
+++ b/scripts/crosstool-NG.sh
@@ -669,7 +669,6 @@ if [ "${CT_ONLY_DOWNLOAD}" != "y" -a "${CT_ONLY_EXTRACT}" != "y" ]; then
     do_stop=0
     prev_step=
     [ -n "${CT_RESTART}" ] && do_it=0 || do_it=1
-    # Aha! CT_STEPS comes from steps.mk!
     for step in ${CT_STEPS}; do
         if [ ${do_it} -eq 0 ]; then
             if [ "${CT_RESTART}" = "${step}" ]; then
diff --git a/scripts/functions b/scripts/functions
index 65a74c2..6e54582 100644
--- a/scripts/functions
+++ b/scripts/functions
@@ -23,7 +23,7 @@ CT_LoadConfig() {
     . "${CT_LIB_DIR}/scripts/build/kernel/${CT_KERNEL}.sh"
     . "${CT_LIB_DIR}/scripts/build/companion_libs.sh"
     . "${CT_LIB_DIR}/scripts/build/binutils/${CT_BINUTILS}.sh"
-    . "${CT_LIB_DIR}/scripts/build/libc/${CT_LIBC}.sh"
+    . "${CT_LIB_DIR}/scripts/build/libc.sh"
     . "${CT_LIB_DIR}/scripts/build/cc/${CT_CC}.sh"
     . "${CT_LIB_DIR}/scripts/build/debug.sh"
     . "${CT_LIB_DIR}/scripts/build/test_suite.sh"
@@ -1095,11 +1095,6 @@ CT_DoBuildTargetTuple() {
         uClibc)   CT_TARGET_SYS=uclibc;;
         musl)     CT_TARGET_SYS=musl;;
         bionic)   CT_TARGET_SYS=android;;
-        avr-libc)
-            # avr-libc only seems to work with the non-canonical "avr" target.
-            CT_TARGET_SKIP_CONFIG_SUB=y
-            CT_TARGET_SYS= # CT_TARGET_SYS must be empty too
-            ;;
         none|newlib)
             CT_TARGET_SYS=elf
             ;;
@@ -1989,6 +1984,7 @@ CT_PackageRun()
             src_release mirrors archive_filename archive_dirname archive_formats signature_format \
             src_devel devel_vcs devel_url devel_branch devel_revision devel_subdir devel_bootstrap \
             src_custom custom_location patch_order; do
+        CT_DoLog DEBUG "Package iterator: set ${v}=\${CT_${use}_${v^^}}"
         eval "local ${v}=\${CT_${use}_${v^^}}"
     done
 
@@ -2004,6 +2000,7 @@ CT_PackageRun()
         eval "eval ${v}=\${${v}//@/$}"
     done
 
+    CT_DoLog DEBUG "Package iterator: run ${run} $*"
     ${run} "$@"
 
     # Save certain variables that may be modified by the callback.
@@ -2369,7 +2366,10 @@ CT_GetPkgBuildVersion()
     fi
 
     __do_GetPkgBuildVersion() {
-        tmp="${pkg_name}-${version}"
+        tmp="${pkg_name}"
+        if [ "${version}" != "unknown" ]; then
+            tmp+="-${version}"
+        fi
         if [ "${src_devel}" = "y" ]; then
             tmp+="-${devel_vcs}"
             if [ -n "${devel_revision}" ]; then
@@ -2387,18 +2387,6 @@ CT_GetPkgBuildVersion()
     eval "${var}=\"${tmp}\""
 }
 
-# Get a package version as selected by a generated choice in kconfig.
-CT_GetChoicePkgBuildVersion()
-{
-    local choice="${1}"
-    local var="${2}"
-    local component
-
-    # Find the selected component
-    eval "component=\${CT_${choice}_CHOICE_KSYM}"
-    CT_GetPkgBuildVersion "${choice}" "${component}" "${var}"
-}
-
 # Finally, load paths.sh. For --enable-local build, it is located in
 # the current directory (CT_TOP_DIR) while the rest of the scripts are
 # in the source directory (CT_LIB_DIR). For other setups, paths.sh
diff --git a/scripts/show-config.sh b/scripts/show-config.sh
index 7f2051c..4bc82e1 100644
--- a/scripts/show-config.sh
+++ b/scripts/show-config.sh
@@ -20,34 +20,27 @@ dump_pkgs_desc()
 {
     local category="${1}"
     local field="${2}"
+    local pkgs
     shift 2
     local show_version
-    local tmp
+    local tmp p
 
+    eval "pkgs=\"\${CT_ALL_${category}_CHOICES}\""
     printf "    %-*s :" ${fieldwidth} "${field}"
-    while [ -n "${1}" ]; do
-        eval "tmp=\"\${CT_${category}_${1}}\""
+    for p in ${pkgs}; do
+        # FIXME: multiple choices use category_package; single choice
+        # use category_package for the primary selection and category_package_SHOW
+        # for all other selections enabled by the primary. Cannot unify this syntax
+        # without a really extensive change.
+        eval "tmp=\"\${CT_${category}_${p}}\${CT_${category}_${p}_SHOW}\""
         if [ -n "${tmp}" ]; then
-            CT_GetPkgBuildVersion "${category}" "${1}" show_version
+            CT_GetPkgBuildVersion "${category}" "${p}" show_version
             printf " %s" "${show_version}"
         fi
-        shift
     done
     printf "\n"
 }
 
-# Dump a short package description with a name and version in a format
-# " <name>[-<version>]"
-dump_choice_desc()
-{
-    local category="${1}"
-    local field="${2}"
-    local show_version
-
-    CT_GetChoicePkgBuildVersion "${category}" show_version
-    printf "    %-*s : %s\n" ${fieldwidth} "${field}" "${show_version}"
-}
-
 # Dump a single sample
 # Note: we use the specific .config.sample config file
 dump_single_sample()
@@ -88,13 +81,6 @@ dump_single_sample()
                 printf "    %-*s : %s\n" ${fieldwidth} "Host" "${CT_HOST}"
                 ;;
         esac
-        # FIXME get choice/menu names from generated kconfig files as well
-        # FIXME get the list of menu components from generated kconfig files
-        dump_choice_desc KERNEL "OS"
-        dump_pkgs_desc COMP_LIBS "Companion libs" GMP MPFR MPC ISL CLOOG LIBELF EXPAT NCURSES \
-                LIBICONV GETTEXT
-        dump_choice_desc BINUTILS "Binutils"
-        dump_choice_desc CC "Compiler"
         printf "    %-*s : %s" ${fieldwidth} "Languages" "C"
         [ "${CT_CC_LANG_CXX}" = "y"     ] && printf ",C++"
         [ "${CT_CC_LANG_FORTRAN}" = "y" ] && printf ",Fortran"
@@ -106,9 +92,13 @@ dump_single_sample()
         [ -n "${CT_CC_LANG_OTHERS}"     ] && printf ",${CT_CC_LANG_OTHERS}"
         printf "\n"
 
-        dump_choice_desc LIBC "C library"
-        dump_pkgs_desc DEBUG "Debug tools" DUMA GDB LTRACE STRACE
-        dump_pkgs_desc COMP_TOOLS "Companion tools" AUTOCONF AUTOMAKE LIBTOOL M4 MAKE DTC
+        dump_pkgs_desc KERNEL "OS"
+        dump_pkgs_desc BINUTILS "Binutils"
+        dump_pkgs_desc CC "Compiler"
+        dump_pkgs_desc LIBC "C library"
+        dump_pkgs_desc DEBUG "Debug tools"
+        dump_pkgs_desc COMP_LIBS "Companion libs"
+        dump_pkgs_desc COMP_TOOLS "Companion tools"
     fi
 }