[gnumeric] Compilation: fix problem with non-compile-time constant

[Morten Welinder <mortenw src gnome org>]

commit 3672284de109f93629c53f97e6ba22a60b399a70
Author: Morten Welinder <terra gnome org>
Date:   Tue Jan 15 07:39:20 2019 -0500

    Compilation: fix problem with non-compile-time constant

 ChangeLog      | 5 +++++
 NEWS           | 3 +++
 src/mathfunc.c | 2 +-
 3 files changed, 9 insertions(+), 1 deletion(-)
---
diff --git a/ChangeLog b/ChangeLog
index 7c41e52e4..f62478899 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2019-01-15  Morten Welinder  <terra gnome org>
+
+       * src/mathfunc.c (gnm_lambert_w): Avoid static for something that
+       formally isn't a compile-time constant.  [#378]
+
 2018-11-24  Morten Welinder <terra gnome org>
 
        * configure.ac: Post-release bump.
diff --git a/NEWS b/NEWS
index 1e7957ac5..b08f75aa6 100644
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,9 @@ Morten:
        * Add DIGAMMA function.
        * Support ISO-8601 UTC date/time input.  Mostly.  [#371]
 
+Thomas Klausner:
+       * Fix compilation issue.  [#378]
+
 --------------------------------------------------------------------------
 Gnumeric 1.12.44
 
diff --git a/src/mathfunc.c b/src/mathfunc.c
index e5360891a..7ab0b9c57 100644
--- a/src/mathfunc.c
+++ b/src/mathfunc.c
@@ -5034,7 +5034,7 @@ gnm_lambert_w (gnm_float x, int k)
 {
        gnm_float w;
        static const gnm_float one_over_e = 1 / M_Egnum;
-       static const gnm_float sqrt_one_over_e = gnm_sqrt (1 / M_Egnum);
+       const gnm_float sqrt_one_over_e = gnm_sqrt (1 / M_Egnum);
        static const gboolean debug = FALSE;
        gnm_float wmin, wmax;
        int i, imax = 20;