trees: match gcc/gnat versions both ways

on debian trixie/sid after updating from stable,
sometimes gcc 13 and gnat 13 are both available, but
gcc resolves to gcc-14 and gnat-14 isn't available.

even when gnat-14 and gcc-14 are available, gnat will
still either resolve to gnat-13, or nothing at all.

in cases where gnat-14 is unavailable, but gcc and gnat 13
are both available, we should match gcc to gnat.

Signed-off-by: Leah Rowe <leah@libreboot.org>

1 files changed, 40 insertions, 24 deletions

diff --git a/script/trees b/script/trees
index 786461dc..d07f3254 100755
--- a/script/trees
+++ b/script/trees
@@ -15,7 +15,7 @@ eval `setvars "" xarch srcdir premake cmakedir xlang mode makeargs elfdir cmd \
     project target target_dir targets xtree _f release bootstrapargs mkhelper \
     autoconfargs listfile autogenargs btype tree rev tree_depend build_depend \
     defconfig postmake mkhelpercfg dry dest_dir mdir cleanargs gccver gccfull \
-    gnatver gnatfull gccdir`; badhash="n"
+    gnatver gnatfull gccdir gnatdir`; badhash="n"
 
 main()
 {
@@ -206,7 +206,11 @@ check_cross_compiler()
 
 		xfix="${_xarch%-*}" && [ "$xfix" = "x86_64" ] && xfix="x64"
 
-		check_gnat_path
+		# match gnat-X to gcc
+		(
+		check_gnu_path gcc gnat || check_gnu_path gnat gcc || \
+		    $err "Host GCC/GNAT mismatch"
+		) || $err "Cannot match host GCC/GNAT versions"
 
 		# sometimes buildgcc fails for like no reason. try twice.
 		make -C "$cbdir" crossgcc-$xfix $xgccargs || \
@@ -215,43 +219,55 @@ check_cross_compiler()
 	done; return 0
 }
 
-# fix mismatching gcc/gnat versions on debian trixie/sid
-check_gnat_path()
+# fix mismatching gcc/gnat versions on debian trixie/sid. as of december 2024,
+# trixie/sid had gnat-13 as gnat and gcc-14 as gcc, but has gnat-14 in apt. in
+# some cases, gcc 13+14 and gnat-13 are present; or gnat-14 and gcc-14, but
+# gnat in PATH never resolves to gnat-14, because gnat-14 was "experimental"
+check_gnu_path()
 {
-	rm -f xbmkpath/* || $err "Cannot clear xbmkpath/"
+	[ $# -lt 2 ] && $err "check_gnu_path: Too few arguments"
+	[ "$1" = "$2" ] && $err "check_gnu_path: Both arguments identical"
+	for _gnuarg in 1 2; do
+		eval "[ \"\$$_gnuarg\" = \"gcc\" ] && continue"
+		eval "[ \"\$$_gnuarg\" = \"gnat\" ] && continue"
+		$err "check_gnu_path: Invalid argument \"$_gnuarg\""
+	done
+	command -v $1 1>/dev/null || $err "Host gcc unavailable"
 
-	eval `setvars "" gccver gccfull gnatver gnatfull gccdir`
-	gnu_setver gcc gcc || $err "Command 'gcc' unavailable."
-	gnu_setver gnat gnat || :
+	eval `setvars "" gccver gccfull gnatver gnatfull gccdir gnatdir`
+	gnu_setver "$1" "$1" || $err "Command '$1' unavailable."
+	gnu_setver "$2" "$2" || :
 
-	[ -z "$gccver" ] && $err "Cannot detect host GCC version"
+	eval "[ -z \"\$$1ver\" ] && $err \"Cannot detect host '$1' version\""
 	[ "$gnatfull" = "$gccfull" ] && return 0
 
-	gccdir="$(dirname "$(command -v gcc)")"
-	for _gnatbin in "$gccdir/gnat-"*; do
-		[ -f "$_gnatbin" ] || continue
-		[ "${_gnatbin#"$gccdir/gnat-"}" = "$gccver" ] || continue
-		gnatver="${_gnatbin#"$gccdir/gnat-"}"; break
+	eval "$1dir="$(dirname "$(command -v $1)")""
+	eval "_gnudir=\"\$$1dir\"; _gnuver=\"\$$1ver\""
+	for _gnubin in "$_gnudir/$2-"*; do
+		[ -f "$_gnubin" ] || continue
+		[ "${_gnubin#"$_gnudir/$2-"}" = "$_gnuver" ] || continue
+		gnatver="${_gnubin#"$_gnudir/$2-"}"; break
 	done
-	gnu_setver "gnat" "$gccdir/gnat-$gccver" || $err "Unknown gnat version"
-	[ "$gnatfull" = "$gccfull" ] || $err "GCC/GNAT versions do not match."
+	gnu_setver "$2" "$_gnudir/$2-$_gnuver" || return 1
+	[ "$gnatfull" = "$gccfull" ] || return 1
 
 	(
+	rm -f xbmkpath/* || $err "Cannot clear xbmkpath/"
 	x_ cd xbmkpath
-	for _gnatbin in "$gccdir/gnat"*"-$gccver"; do
-		[ -e "$_gnatbin" ] || continue; _gnatutil="${_gnatbin##*/}"
-		x_ ln -s "$_gnatbin" "${_gnatutil%"-$gccver"}"
+	for _gnubin in "$_gnudir/$2"*"-$_gnuver"; do
+		[ -e "$_gnubin" ] || continue; _gnuutil="${_gnubin##*/}"
+		x_ ln -s "$_gnubin" "${_gnuutil%"-$_gnuver"}"
 	done
-	) || $err "Cannot create gnat-$gccver link in $gccdir"; :
+	) || $err "Cannot create $2-$_gnuver link in $_gnudir"; :
 }
 
 gnu_setver()
 {
 	eval "$2 --version 1>/dev/null 2>/dev/null || return 1"
-	eval "${1}ver=\"`$2 --version 2>/dev/null | head -n1`\""
-	eval "${1}ver=\"\${${1}ver##* }\""
-	eval "${1}full=\"\${$1}ver\""
-	eval "${1}ver=\"\${${1}ver%%.*}\""; :
+	eval "$1ver=\"`$2 --version 2>/dev/null | head -n1`\""
+	eval "$1ver=\"\${$1ver##* }\""
+	eval "$1full=\"\$$1ver\""
+	eval "$1ver=\"\${$1ver%%.*}\""; :
 }
 
 check_defconfig()