On Cygwin, the GNU D compiler (gdc) is installed without its standard
library. As a consequence, it cannot compile anything. This leads to build
errors later in GNU gettext.
It is better if the configure test catches this situation and treats it
like if no D compiler is installed. This patch does it.
2025-06-12 Bruno Haible <br...@clisp.org>
dcomp-script: Reject D compilers with installation problems.
* m4/dcomp.m4 (gt_DCOMP): Try each candidate program, seeing whether it
can compile a trivial program.
* build-aux/dcomp.sh.in: Fix typos in comment.
diff --git a/build-aux/dcomp.sh.in b/build-aux/dcomp.sh.in
index 52a6123d22..7500f58c25 100644
--- a/build-aux/dcomp.sh.in
+++ b/build-aux/dcomp.sh.in
@@ -23,11 +23,11 @@
# -c
# -g
# -O (mapped to -O or -O2, depending on implementation)
-# -o FILE (for libtool compatility)
-# -lLIBRARY (for libtool compatility)
-# -LDIR (for libtool compatility)
-# -pthread (for libtool compatility)
-# -Wl,OPTION (for libtool compatility)
+# -o FILE (for libtool compatibility)
+# -lLIBRARY (for libtool compatibility)
+# -LDIR (for libtool compatibility)
+# -pthread (for libtool compatibility)
+# -Wl,OPTION (for libtool compatibility)
# Find out which implementation we are using.
case `@DC@ --version | sed -e 's/ .*//' -e 1q` in
diff --git a/m4/dcomp.m4 b/m4/dcomp.m4
index 4481338813..ff42db1a4d 100644
--- a/m4/dcomp.m4
+++ b/m4/dcomp.m4
@@ -1,5 +1,5 @@
# dcomp.m4
-# serial 2
+# serial 3
dnl Copyright (C) 2025 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -31,7 +31,55 @@ AC_DEFUN([gt_DCOMP]
AC_ARG_VAR([DC], [D compiler command])
AC_ARG_VAR([DFLAGS], [D compiler options])
dnl On OpenBSD, gdc is called 'egdc' and works less well than dmd.
- AC_CHECK_TOOLS([DC], [gdc ldc2 dmd egdc])
+ dnl Like AC_CHECK_TOOLS([DC], [gdc ldc2 dmd egdc]) but check whether the
+ dnl compiler can actually compile a trivial program. We may simplify this
+ dnl once <https://savannah.gnu.org/support/index.php?111256> is implemented.
+ if test -z "$DC"; then
+ echo > empty.d
+ if test -n "${host_alias}"; then
+ if test -z "$DC"; then
+ DC="${host_alias}-gdc"
+ echo "$as_me:${as_lineno-$LINENO}: trying ${DC}..." >&AS_MESSAGE_LOG_FD
+ if ${DC} -c empty.d 2>&AS_MESSAGE_LOG_FD; then :; else DC= ; fi
+ fi
+ if test -z "$DC"; then
+ DC="${host_alias}-ldc2"
+ echo "$as_me:${as_lineno-$LINENO}: trying ${DC}..." >&AS_MESSAGE_LOG_FD
+ if ${DC} -c empty.d 2>&AS_MESSAGE_LOG_FD; then :; else DC= ; fi
+ fi
+ if test -z "$DC"; then
+ DC="${host_alias}-dmd"
+ echo "$as_me:${as_lineno-$LINENO}: trying ${DC}..." >&AS_MESSAGE_LOG_FD
+ if ${DC} -c empty.d 2>&AS_MESSAGE_LOG_FD; then :; else DC= ; fi
+ fi
+ if test -z "$DC"; then
+ DC="${host_alias}-egdc"
+ echo "$as_me:${as_lineno-$LINENO}: trying ${DC}..." >&AS_MESSAGE_LOG_FD
+ if ${DC} -c empty.d 2>&AS_MESSAGE_LOG_FD; then :; else DC= ; fi
+ fi
+ fi
+ if test -z "$DC"; then
+ DC="gdc"
+ echo "$as_me:${as_lineno-$LINENO}: trying ${DC}..." >&AS_MESSAGE_LOG_FD
+ if ${DC} -c empty.d 2>&AS_MESSAGE_LOG_FD; then :; else DC= ; fi
+ fi
+ if test -z "$DC"; then
+ DC="ldc2"
+ echo "$as_me:${as_lineno-$LINENO}: trying ${DC}..." >&AS_MESSAGE_LOG_FD
+ if ${DC} -c empty.d 2>&AS_MESSAGE_LOG_FD; then :; else DC= ; fi
+ fi
+ if test -z "$DC"; then
+ DC="dmd"
+ echo "$as_me:${as_lineno-$LINENO}: trying ${DC}..." >&AS_MESSAGE_LOG_FD
+ if ${DC} -c empty.d 2>&AS_MESSAGE_LOG_FD; then :; else DC= ; fi
+ fi
+ if test -z "$DC"; then
+ DC="egdc"
+ echo "$as_me:${as_lineno-$LINENO}: trying ${DC}..." >&AS_MESSAGE_LOG_FD
+ if ${DC} -c empty.d 2>&AS_MESSAGE_LOG_FD; then :; else DC= ; fi
+ fi
+ rm -f empty.d empty.o empty.obj
+ fi
popdef([AC_MSG_RESULT])dnl
popdef([AC_CHECKING])dnl
popdef([AC_MSG_CHECKING])dnl
