From 81afd17a0876b9aeb00657742b2335837f2b1448 Mon Sep 17 00:00:00 2001
From: Denis Davydov <davydden@gmail.com>
Date: Wed, 27 Apr 2016 07:19:20 +0200
Subject: [PATCH] add and use DEAL_II_WITH_GSL

---
 doc/doxygen/options.dox.in              |  3 ++-
 include/deal.II/base/config.h.in        |  2 +-
 include/deal.II/base/function_cspline.h |  3 +++
 source/base/function_cspline.cc         |  3 +++
 tests/base/functions_cspline.cc         | 13 +++++++++++++
 5 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/doc/doxygen/options.dox.in b/doc/doxygen/options.dox.in
index 6f16b23e37..5dd491948a 100644
--- a/doc/doxygen/options.dox.in
+++ b/doc/doxygen/options.dox.in
@@ -1,4 +1,4 @@
-# This file contains project-specific configurations for the 
+# This file contains project-specific configurations for the
 # deal.II documentation.
 
 PROJECT_NAME           = "The deal.II Library"
@@ -167,6 +167,7 @@ PREDEFINED             = DOXYGEN=1 \
                          DEAL_II_WITH_BOOST=1 \
                          DEAL_II_WITH_CXX11=1 \
                          DEAL_II_WITH_CXX14=1 \
+                         DEAL_II_WITH_GSL=1 \
                          DEAL_II_WITH_HDF5=1 \
                          DEAL_II_WITH_LAPACK=1 \
                          DEAL_II_WITH_METIS=1 \
diff --git a/include/deal.II/base/config.h.in b/include/deal.II/base/config.h.in
index d6c5f0348e..1f8cb03e52 100644
--- a/include/deal.II/base/config.h.in
+++ b/include/deal.II/base/config.h.in
@@ -39,6 +39,7 @@
 #cmakedefine DEAL_II_WITH_BZIP2
 #cmakedefine DEAL_II_WITH_CXX11
 #cmakedefine DEAL_II_WITH_CXX14
+#cmakedefine DEAL_II_WITH_GSL
 #cmakedefine DEAL_II_WITH_HDF5
 #cmakedefine DEAL_II_WITH_LAPACK
 #cmakedefine DEAL_II_WITH_METIS
@@ -331,4 +332,3 @@ _Pragma("GCC diagnostic pop")
 #include <deal.II/base/types.h>
 
 #endif
-
diff --git a/include/deal.II/base/function_cspline.h b/include/deal.II/base/function_cspline.h
index fac6269867..361c7f7464 100644
--- a/include/deal.II/base/function_cspline.h
+++ b/include/deal.II/base/function_cspline.h
@@ -18,6 +18,7 @@
 
 #include <deal.II/base/config.h>
 
+#ifdef DEAL_II_WITH_GSL
 #include <deal.II/base/function.h>
 #include <deal.II/base/point.h>
 #include <gsl/gsl_spline.h>
@@ -111,3 +112,5 @@ DEAL_II_NAMESPACE_CLOSE
 
 #endif
 
+#endif
+
diff --git a/source/base/function_cspline.cc b/source/base/function_cspline.cc
index a74e311ee9..af8df06dd3 100644
--- a/source/base/function_cspline.cc
+++ b/source/base/function_cspline.cc
@@ -16,6 +16,7 @@
 #include <deal.II/base/point.h>
 #include <deal.II/base/function_cspline.h>
 
+#ifdef DEAL_II_WITH_GSL
 #include <cmath>
 #include <algorithm>
 
@@ -97,3 +98,5 @@ namespace Functions
 }
 
 DEAL_II_NAMESPACE_CLOSE
+
+#endif
diff --git a/tests/base/functions_cspline.cc b/tests/base/functions_cspline.cc
index 56338974ed..45952175aa 100644
--- a/tests/base/functions_cspline.cc
+++ b/tests/base/functions_cspline.cc
@@ -21,6 +21,7 @@
 #include <cmath>
 #include <deal.II/base/function_cspline.h>
 
+#ifdef DEAL_II_WITH_GSL
 template <int dim>
 void check()
 {
@@ -77,3 +78,15 @@ int main()
 
   check<1>();
 }
+#else
+
+int main()
+{
+  std::string logname = "output";
+  std::ofstream logfile(logname.c_str());
+  deallog.attach(logfile);
+  deallog.threshold_double(1.e-10);
+
+  deallog << "Ok"<< std::endl;
+}
+#endif
-- 
2.39.5