build: With LD_LIBRARY_PATH defined, use --disable-new-dtags.

* configure.ac (LDADD_FOR_TESTS_KLUDGE): New for --disable-new-dtags.
* tests/Makefile.am (LDADD): Use LDADD_FOR_TESTS_KLUDGE.

--

GnuPG-bug-id: 4298
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>

1 files changed, 35 insertions, 0 deletions

diff --git a/configure.ac b/configure.ac
index 1298eb1..53a4ac6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -85,6 +85,41 @@ AB_INIT
 
 AC_GNU_SOURCE
 
+# Taken from mpfr-4.0.1, then modified for LDADD_FOR_TESTS_KLUDGE
+dnl Under Linux, make sure that the old dtags are used if LD_LIBRARY_PATH
+dnl is defined. The issue is that with the new dtags, LD_LIBRARY_PATH has
+dnl the precedence over the run path, so that if a compatible MPFR library
+dnl is installed in some directory from $LD_LIBRARY_PATH, then the tested
+dnl MPFR library will be this library instead of the MPFR library from the
+dnl build tree. Other OS with the same issue might be added later.
+dnl
+dnl References:
+dnl   https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=859732
+dnl   http://lists.gnu.org/archive/html/libtool/2017-05/msg00000.html
+dnl
+dnl We need to check whether --disable-new-dtags is supported as alternate
+dnl linkers may be used (e.g., with tcc: CC=tcc LD=tcc).
+dnl
+case $host in
+  *-*-linux*)
+    if test -n "$LD_LIBRARY_PATH"; then
+      saved_LDFLAGS="$LDFLAGS"
+      LDADD_FOR_TESTS_KLUDGE="-Wl,--disable-new-dtags"
+      LDFLAGS="$LDFLAGS $LDADD_FOR_TESTS_KLUDGE"
+      AC_MSG_CHECKING(whether --disable-new-dtags is supported by the linker)
+      AC_LINK_IFELSE([AC_LANG_SOURCE([[
+int main (void) { return 0; }
+      ]])],
+      [AC_MSG_RESULT(yes (use it since LD_LIBRARY_PATH is set))],
+      [AC_MSG_RESULT(no)
+       LDADD_FOR_TESTS_KLUDGE=""
+      ])
+      LDFLAGS="$saved_LDFLAGS"
+    fi
+    ;;
+esac
+AC_SUBST([LDADD_FOR_TESTS_KLUDGE])
+
 VERSION_NUMBER=m4_esyscmd(printf "0x%02x%02x%02x" mym4_major \
                           mym4_minor mym4_micro)
 AC_SUBST(VERSION_NUMBER)