PP: Partially address issue #738: handle premature end of argument when token pasting.

Test/baseResults/tokenPaste.vert.out

@@ -5,7 +5,10 @@ ERROR: 0:40: '##' : unexpected location; end of replacement list
 ERROR: 0:49: '##' : combined tokens are too long 
 ERROR: 0:52: '##' : not supported for these tokens 
 ERROR: 0:69: '##' : combined token is invalid 
-ERROR: 5 compilation errors.  No code generated.
+ERROR: 0:82: 'macro expansion' : Too few args in Macro rec
+ERROR: 0:82: '##' : unexpected location 
+ERROR: 0:82: '##' : unexpected location 
+ERROR: 8 compilation errors.  No code generated.
 
 
 Shader version: 450

Test/tokenPaste.vert

@@ -77,3 +77,6 @@ uniform M_OUTER(argPaste);
 #define M_NEST2(q) int q ## suff
 #define M_OUTER2(p) M_NEST2(p ## 20)
 uniform M_OUTER2(argPaste);
+
+#define rec(x)##
+rec(rec())
\ No newline at end of file

glslang/Include/revision.h

@@ -2,5 +2,5 @@
 // For the version, it uses the latest git tag followed by the number of commits.
 // For the date, it uses the current date (when then script is run).
 
-#define GLSLANG_REVISION "Overload400-PrecQual.1858"
+#define GLSLANG_REVISION "Overload400-PrecQual.1861"
 #define GLSLANG_DATE "28-Feb-2017"

glslang/MachineIndependent/preprocessor/Pp.cpp

@@ -986,6 +986,8 @@ TPpContext::TokenStream* TPpContext::PrescanMacroArg(TokenStream& arg, TPpToken*
     int token;
     while ((token = scanToken(ppToken)) != tMarkerInput::marker && token != EndOfInput) {
         token = tokenPaste(token, *ppToken);
+        if (token == tMarkerInput::marker || token == EndOfInput)
+            break;
         if (token == PpAtomIdentifier && MacroExpand(ppToken, false, newLineOkay) != 0)
             continue;
         expandedArg->putToken(token, ppToken);