3 files changed, 12 insertions, 8 deletions
diff --git a/gr-analog/include/analog/sincos.h b/gr-analog/include/analog/sincos.h
index c262434f0..38b9d96da 100644
--- a/gr-analog/include/analog/sincos.h
+++ b/gr-analog/include/analog/sincos.h
@@ -27,19 +27,11 @@
 
 namespace gr {
   namespace analog {
-    
-#ifdef __cplusplus
-extern "C" {
-#endif
 
   // compute sine and cosine at the same time
   ANALOG_API void sincos(double x, double *sin, double *cos);
   ANALOG_API void sincosf(float x, float *sin, float *cos);
 
-#ifdef __cplusplus
-};
-#endif
-
   } /* namespace analog */
 } /* namespace gr */
 
diff --git a/gr-analog/lib/CMakeLists.txt b/gr-analog/lib/CMakeLists.txt
index 5e7d131b0..aaf3c8656 100644
--- a/gr-analog/lib/CMakeLists.txt
+++ b/gr-analog/lib/CMakeLists.txt
@@ -131,6 +131,7 @@ list(APPEND analog_sources
     quadrature_demod_cf_impl.cc
     rail_ff_impl.cc
     simple_squelch_cc_impl.cc
+    sincos.cc
 )
 
 list(APPEND analog_libs
@@ -174,3 +175,11 @@ if(ENABLE_TESTING)
 
   GR_ADD_TEST(test_gr_analog test-gr-analog)
 endif(ENABLE_TESTING)
+
+CHECK_CXX_SOURCE_COMPILES("
+    #define _GNU_SOURCE
+    #include <math.h>
+    int main(){double x, sin, cos; sincos(x, &sin, &cos); return 0;}
+    " HAVE_SINCOS
+)
+GR_ADD_COND_DEF(HAVE_SINCOS)
diff --git a/gr-analog/lib/sincos.cc b/gr-analog/lib/sincos.cc
index aa72b1cd4..f3d385611 100644
--- a/gr-analog/lib/sincos.cc
+++ b/gr-analog/lib/sincos.cc
@@ -84,3 +84,6 @@ namespace gr {
     }
 
 #endif
+
+  } /* namespace analog */
+} /* namespace gr */