Improve support for older C++ compilers

Some current  Linux distributions  are still using  GCC 4.6  which has
no/poor  C++11 support.  probably more  of this  needed if  we are  to
support such compilers.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@7896 ab8295b8-cf94-4d9e-aec4-7959e3be5d79

lib/crc10.cpp

@@ -1,24 +1,31 @@
-#include <boost/crc.hpp>
-
-extern "C"
-{
-   short crc10 (unsigned char const * data, int length);
-   bool crc10_check (unsigned char const * data, int length);
-}
-
-namespace
-{
-  unsigned long constexpr truncated_polynomial = 0x08f;
-}
-
-// assumes CRC is last 16 bits of the data and is set to zero
-// caller should assign the returned CRC into the message in big endian byte order
-short crc10 (unsigned char const * data, int length)
-{
-    return boost::augmented_crc<10, truncated_polynomial> (data, length);
-}
-
-bool crc10_check (unsigned char const * data, int length)
-{
-   return !boost::augmented_crc<10, truncated_polynomial> (data, length);
-}
+#include <boost/crc.hpp>
+#include <boost/config.hpp>
+
+extern "C"
+{
+   short crc10 (unsigned char const * data, int length);
+   bool crc10_check (unsigned char const * data, int length);
+}
+
+#define POLY 0x08f
+
+#ifdef BOOST_NO_CXX11_CONSTEXPR
+#define TRUNCATED_POLYNOMIAL POLY
+#else
+namespace
+{
+  unsigned long constexpr TRUNCATED_POLYNOMIAL = POLY;
+}
+#endif
+
+// assumes CRC is last 16 bits of the data and is set to zero
+// caller should assign the returned CRC into the message in big endian byte order
+short crc10 (unsigned char const * data, int length)
+{
+    return boost::augmented_crc<10, TRUNCATED_POLYNOMIAL> (data, length);
+}
+
+bool crc10_check (unsigned char const * data, int length)
+{
+   return !boost::augmented_crc<10, TRUNCATED_POLYNOMIAL> (data, length);
+}