Fix -ferror-limit= to properly emit notes following the last error

messages. Fi from David Blaikie, tests from Nikola Smiljanic!

llvm-svn: 137851

3 files changed, 44 insertions, 4 deletions

diff --git a/clang/lib/Basic/DiagnosticIDs.cpp b/clang/lib/Basic/DiagnosticIDs.cpp
index 907e826a33c..fa397c9ac93 100644
--- a/clang/lib/Basic/DiagnosticIDs.cpp
+++ b/clang/lib/Basic/DiagnosticIDs.cpp
@@ -733,11 +733,13 @@ bool DiagnosticIDs::ProcessDiag(Diagnostic &Diag) const {
       ++Diag.NumErrors;
     }
 
-    // If we've emitted a lot of errors, emit a fatal error after it to stop a
-    // flood of bogus errors.
-    if (Diag.ErrorLimit && Diag.NumErrors >= Diag.ErrorLimit &&
-        DiagLevel == DiagnosticIDs::Error)
+    // If we've emitted a lot of errors, emit a fatal error instead of it to 
+    // stop a flood of bogus errors.
+    if (Diag.ErrorLimit && Diag.NumErrors > Diag.ErrorLimit &&
+        DiagLevel == DiagnosticIDs::Error) {
       Diag.SetDelayedDiagnostic(diag::fatal_too_many_errors);
+      return false;
+    }
   }
 
   // If we have any Fix-Its, make sure that all of the Fix-Its point into
diff --git a/clang/test/Misc/error-limit-multiple-notes.cpp b/clang/test/Misc/error-limit-multiple-notes.cpp
new file mode 100644
index 00000000000..019b4dde263
--- /dev/null
+++ b/clang/test/Misc/error-limit-multiple-notes.cpp
@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 -ferror-limit 1 -fsyntax-only %s 2>&1 | FileCheck %s
+
+// error and three notes emitted
+void foo(int);
+void foo(double);
+void foo(int, int);
+
+int main()
+{
+    foo();
+}
+
+// error and note suppressed by error-limit
+struct s1{};
+struct s1{};
+
+// CHECK: 10:5: error: no matching function for call to 'foo'
+// CHECK: 6:6: note: candidate function not viable: requires 2 arguments, but 0 were provided
+// CHECK: 5:6: note: candidate function not viable: requires 1 argument, but 0 were provided
+// CHECK: 4:6: note: candidate function not viable: requires 1 argument, but 0 were provided
+// CHECK: fatal error: too many errors emitted, stopping now
+// CHECK-NOT: 15:8: error: redefinition of 's1'
+// CHECK-NOT: 14:8: note: previous definition is here
diff --git a/clang/test/Misc/error-limit.c b/clang/test/Misc/error-limit.c
new file mode 100644
index 00000000000..26f4ac1d8a5
--- /dev/null
+++ b/clang/test/Misc/error-limit.c
@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 -ferror-limit 1 -fsyntax-only %s 2>&1 | FileCheck %s
+
+// error and note emitted
+struct s1{};
+struct s1{};
+
+// error and note suppressed by error-limit
+struct s2{};
+struct s2{};
+
+// CHECK: 5:8: error: redefinition of 's1'
+// CHECK: 4:8: note: previous definition is here
+// CHECK: fatal error: too many errors emitted, stopping now
+// CHECK-NOT: 9:8: error: redefinition of 's2'
+// CHECK-NOT: 8:8: note: previous definition is here