PP: Fix issue #408: # as last character in macro.

This would look ahead for a second #, for token pasting, and if not
found, backup one token.  This is fine, unless at the end of line,
which would backup the #, rather than the look ahead.

Test/baseResults/cppBad.vert.out

@@ -0,0 +1,20 @@
+cppBad.vert
+ERROR: 0:2: 'preprocessor evaluation' : bad expression 
+ERROR: 0:2: '#if' : unexpected tokens following directive 
+ERROR: 0:3: '' : missing #endif 
+ERROR: 3 compilation errors.  No code generated.
+
+
+Shader version: 100
+ERROR: node is still EOpNull!
+0:?   Linker Objects
+
+
+Linked vertex stage:
+
+ERROR: Linking vertex stage: Missing entry point: Each stage requires one "void main()" entry point
+
+Shader version: 100
+ERROR: node is still EOpNull!
+0:?   Linker Objects
+

Test/cppBad.vert

@@ -0,0 +1,2 @@
+#define m#0#
+#if m

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 "SPIRV99.1367"
+#define GLSLANG_REVISION "SPIRV99.1370"
 #define GLSLANG_DATE "30-Jul-2016"

glslang/MachineIndependent/preprocessor/PpTokens.cpp

@@ -180,14 +180,17 @@ int TPpContext::ReadToken(TokenStream *pTok, TPpToken *ppToken)
         ltoken += 128;
     switch (ltoken) {
     case '#':
-        if (lReadByte(pTok) == '#') {
-            parseContext.requireProfile(ppToken->loc, ~EEsProfile, "token pasting (##)");
-            parseContext.profileRequires(ppToken->loc, ~EEsProfile, 130, 0, "token pasting (##)");
-            parseContext.error(ppToken->loc, "token pasting not implemented (internal error)", "##", "");
-            //return PpAtomPaste;
-            return ReadToken(pTok, ppToken);
-        } else
-            lUnreadByte(pTok);
+        // Check for ##, unless the current # is the last character
+        if (pTok->current < pTok->data.size()) {
+            if (lReadByte(pTok) == '#') {
+                parseContext.requireProfile(ppToken->loc, ~EEsProfile, "token pasting (##)");
+                parseContext.profileRequires(ppToken->loc, ~EEsProfile, 130, 0, "token pasting (##)");
+                parseContext.error(ppToken->loc, "token pasting not implemented (internal error)", "##", "");
+                //return PpAtomPaste;
+                return ReadToken(pTok, ppToken);
+            } else
+                lUnreadByte(pTok);
+        }
         break;
     case PpAtomConstString:
     case PpAtomIdentifier:

gtests/AST.FromFile.cpp

@@ -78,6 +78,7 @@ INSTANTIATE_TEST_CASE_P(
         "cppSimple.vert",
         "cppIndent.vert",
         "cppNest.vert",
+        "cppBad.vert",
         "cppComplexExpr.vert",
         "badChars.frag",
         "pointCoord.frag",