Introduce a limit on the depth of the macro instantiation backtrace

printed in a diagnostic, similar to the limit we already have on the
depth of the template instantiation backtrace. The macro instantiation
backtrace is limited to 10 "instantiated from:" diagnostics; when it's
longer than that, we'll show the first half, then say how many were
suppressed, then show the second half. The limit can be changed with
-fmacro-instantiation-limit=N, and turned off with N=0.

This eliminates a lot of note spew with libraries making use of the
Boost.Preprocess library.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@103014 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 1 deletions

diff --git a/include/clang/Frontend/DiagnosticOptions.h b/include/clang/Frontend/DiagnosticOptions.h
index 797cb34023..b4f147bde7 100644
--- a/include/clang/Frontend/DiagnosticOptions.h
+++ b/include/clang/Frontend/DiagnosticOptions.h
@@ -39,11 +39,15 @@ public:
                                  /// deserialized by, e.g., the CIndex library.
 
   unsigned ErrorLimit;           /// Limit # errors emitted.
+  unsigned MacroBacktraceLimit;  /// Limit depth of macro instantiation 
+                                 /// backtrace.
   unsigned TemplateBacktraceLimit; /// Limit depth of instantiation backtrace.
 
   /// The distance between tab stops.
   unsigned TabStop;
-  enum { DefaultTabStop = 8, MaxTabStop = 100 };
+  enum { DefaultTabStop = 8, MaxTabStop = 100, 
+         DefaultMacroBacktraceLimit = 6,
+         DefaultTemplateBacktraceLimit = 10 };
 
   /// Column limit for formatting message diagnostics, or 0 if unused.
   unsigned MessageLength;
@@ -75,6 +79,7 @@ public:
     BinaryOutput = 0;
     ErrorLimit = 0;
     TemplateBacktraceLimit = 0;
+    MacroBacktraceLimit = 0;
   }
 };