Add support for C++17 hexadecimal floating literals

Examples/test-suite/common.mk

@@ -163,6 +163,7 @@ CPP_TEST_CASES += \
 	cpp_static \
 	cpp_typedef \
 	cpp14_binary_integer_literals \
+	cpp17_hex_floating_literals \
 	cpp17_nested_namespaces \
 	cpp17_nspace_nested_namespaces \
 	cpp17_u8_char_literals \

Examples/test-suite/cpp17_hex_floating_literals.i

@@ -0,0 +1,43 @@
+%module cpp17_hex_floating_literals
+
+// Tests are designed so that code compiles with C++98 compilers
+
+%{
+#if __cplusplus >= 201703L
+#define CPP17 1
+#endif
+%}
+
+double f1 = 0x.0p1;
+double f2 = 0x0.p1;
+double f3 = 0x0.0p-1;
+double f4 = 0xf.p-1;
+double f5 = 0xA.0p1;
+double f6 = 0x0.10P+10;
+double f7 = 0xb2F.p2;
+float f8 = 0x1234AP1F;
+float f9 = 0x45A1.D1A2p+10f;
+
+%{
+#if defined(CPP17)
+double f1 = 0x.0p1;
+double f2 = 0x0.p1;
+double f3 = 0x0.0p-1;
+double f4 = 0xf.p-1;
+double f5 = 0xA.0p1;
+double f6 = 0x0.10P+10;
+double f7 = 0xb2F.p2;
+float f8 = 0x1234AP1F;
+float f9 = 0x45A1.D1A2p+10f;
+#else
+double f1 = 0.;
+double f2 = 0.;
+double f3 = 0.;
+double f4 = 7.5;
+double f5 = 20.;
+double f6 = 64.;
+double f7 = 11452.;
+float f8 = 149140.f;
+float f9 = 18253638.f;
+#endif
+%}

Examples/test-suite/python/cpp17_hex_floating_literals_runme.py

@@ -0,0 +1,28 @@
+from cpp17_hex_floating_literals import *
+
+if cvar.f1 != 0.:
+    raise RuntimeError
+
+if cvar.f2 != 0.:
+    raise RuntimeError
+
+if cvar.f3 != 0.:
+    raise RuntimeError
+
+if cvar.f4 != 7.5:
+    raise RuntimeError
+
+if cvar.f5 != 20.:
+    raise RuntimeError
+
+if cvar.f6 != 64.:
+    raise RuntimeError
+
+if cvar.f7 != 11452.:
+    raise RuntimeError
+
+if cvar.f8 != 149140.:
+    raise RuntimeError
+
+if cvar.f9 != 18253638.:
+    raise RuntimeError