[Bug preprocessor/36320] Required diagnosis of syntax error missed

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36320

Bug 36320 depends on bug 36453, which changed state.

Bug 36453 Summary: [DR 412] PR36320 breaks boost
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36453

           What    |Removed                     |Added
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             Status|RESOLVED                    |REOPENED
         Resolution|INVALID                     |---