interface: Declare extern C lib

Now we declare extern C for all compilers and hope this works.

Signed-off-by: Johannes Demel <[email protected]>

Author: jdemel

include/volk/volk_common.h

@@ -76,8 +76,9 @@
 ////////////////////////////////////////////////////////////////////////
 // C-linkage declaration macros
 // FIXME: due to the usage of complex.h, require gcc for c-linkage
+// Hope and p*** that extern "C" works for all relevant compilers nowadays.
 ////////////////////////////////////////////////////////////////////////
-#if defined(__cplusplus) && (__GNUC__)
+#if defined(__cplusplus)
 #define __VOLK_DECL_BEGIN extern "C" {
 #define __VOLK_DECL_END }
 #else