[gnumeric] configure: fix checks related for --with-long-double

[Morten Welinder <mortenw src gnome org>]

commit 65b79b31b6e3f56523b410e49ab9e6357b303242
Author: Morten Welinder <terra gnome org>
Date:   Mon Jul 1 19:15:45 2013 -0400

    configure: fix checks related for --with-long-double

 ChangeLog    |    5 +++++
 NEWS         |    1 +
 configure.ac |    2 +-
 3 files changed, 7 insertions(+), 1 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 70d09fd..64e2363 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2013-07-01  Morten Welinder  <terra gnome org>
+
+       * configure.ac (long double): Crude use -lm for long double
+       function checks.  Fixes #703397.
+
 2013-06-26  Andreas J. Guelzow <aguelzow pyrshep ca>
 
        * src/expr.c (gnm_expr_list_copy): new
diff --git a/NEWS b/NEWS
index 67ee073..c4ba93f 100644
--- a/NEWS
+++ b/NEWS
@@ -16,6 +16,7 @@ Jean:
 Morten:
        * Improve accuracy for 2-argument ERF.
        * Fix crashes on corrupted files.  [#703143] [#703307]
+       * Fix --with-long-double tests.  [#703397]
 
 --------------------------------------------------------------------------
 Gnumeric 1.12.3
diff --git a/configure.ac b/configure.ac
index 7ea193d..1616aed 100644
--- a/configure.ac
+++ b/configure.ac
@@ -624,7 +624,7 @@ AC_ARG_WITH(long_double,
                SAVE_CFLAGS="$CFLAGS"
                SAVE_LIBS="$LIBS"
                CFLAGS="$GNUMERIC_CFLAGS"
-               LIBS="$GNUMERIC_LIBS"
+               LIBS="$GNUMERIC_LIBS -lm"
 
                AC_CHECK_HEADERS(sunmath.h)