configure: canonicalize CHOST.

Fixes https://github.com/zlib-ng/zlib-ng/issues/666
for all the CHOST values currently used in
.github/workflows/*.yml.

Also make ci's shellcheck happy by avoiding backticks in the changed lines.

diff --git a/config.sub b/config.sub
new file mode 100755 (executable)
index 0000000..3d50a16
--- /dev/null
+++ b/config.sub
@@ -0,0 +1,17 @@
+#!/bin/sh
+# Canonicalize CHOST.
+# In particular, converts Debian multiarch tuples into GNU triplets.
+# See also
+#  https://wiki.debian.org/Multiarch/Tuples
+#  https://wiki.gentoo.org/wiki/CHOST
+# If you need an architecture not listed here, file a bug at github.com/zlib-ng/zlib-ng
+# and work around the problem by dropping libtool's much more comprehensive config.sub
+# on top of this file, see
+# https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.sub
+
+case "$1" in
+*-*-linux-gnu) echo $1;;
+i686-linux-gnu|x86_64-linux-gnu*) echo $1 | sed 's/-linux-gnu/-pc-linux-gnu/';;
+*-linux-gnu*) echo $1 | sed 's/-linux-gnu/-unknown-linux-gnu/';;
+*) echo $1;;
+esac

diff --git a/configure b/configure
index 2cc591c115191c09932d4d5b0efbbf71f120225b..d9ff8256334b04428dcffc2e8491e24cd93d3068 100755 (executable)
--- a/configure
+++ b/configure
@@ -23,9 +23,11 @@ BUILDDIR=$(pwd)
 
 # set command prefix for cross-compilation
 if [ -n "${CHOST}" ]; then
-    uname="`echo "${CHOST}" | sed -e 's/^[^-]*-\([^-]*\)$/\1/' -e 's/^[^-]*-[^-]*-\([^-]*\)$/\1/' -e 's/^[^-]*-[^-]*-\([^-]*\)-.*$/\1/'`"
+    # normalize the chost before parsing it
+    NORM_CHOST=$(sh "$SRCDIR"/config.sub $CHOST)
+    uname="$(echo "${NORM_CHOST}" | sed -e 's/^[^-]*-\([^-]*\)$/\1/' -e 's/^[^-]*-[^-]*-\([^-]*\)$/\1/' -e 's/^[^-]*-[^-]*-\([^-]*\)-.*$/\1/')"
     CROSS_PREFIX="${CHOST}-"
-    ARCH="`echo "${CHOST}" | sed -e 's/-.*//'`"
+    ARCH="$(echo "${NORM_CHOST}" | sed -e 's/-.*//')"
 else
     ARCH="`uname -m`"
 fi