Teach the diagnostic engine to provide more detailed information about
how to handle a diagnostic during template argument deduction, which
may be "substitution failure", "suppress", or "report". This keeps us
from, e.g., emitting warnings while performing template argument
deduction.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@99560 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/Diagnostic.h b/include/clang/Basic/Diagnostic.h
index 13e22a0..bce43c2 100644
--- a/include/clang/Basic/Diagnostic.h
+++ b/include/clang/Basic/Diagnostic.h
@@ -389,6 +389,28 @@
/// the diagnostic, this returns null.
static const char *getWarningOptionForDiag(unsigned DiagID);
+ /// \brief Enumeration describing how the the emission of a diagnostic should
+ /// be treated when it occurs during C++ template argument deduction.
+ enum SFINAEResponse {
+ /// \brief The diagnostic should not be reported, but it should cause
+ /// template argument deduction to fail.
+ ///
+ /// The vast majority of errors that occur during template argument
+ /// deduction fall into this category.
+ SFINAE_SubstitutionFailure,
+
+ /// \brief The diagnostic should be suppressed entirely.
+ ///
+ /// Warnings generally fall into this category.
+ SFINAE_Suppress,
+
+ /// \brief The diagnostic should be reported.
+ ///
+ /// The diagnostic should be reported. Various fatal errors (e.g.,
+ /// template instantiation depth exceeded) fall into this category.
+ SFINAE_Report
+ };
+
/// \brief Determines whether the given built-in diagnostic ID is
/// for an error that is suppressed if it occurs during C++ template
/// argument deduction.
@@ -397,7 +419,7 @@
/// deduction fails but no diagnostic is emitted. Certain classes of
/// errors, such as those errors that involve C++ access control,
/// are not SFINAE errors.
- static bool isBuiltinSFINAEDiag(unsigned DiagID);
+ static SFINAEResponse getDiagnosticSFINAEResponse(unsigned DiagID);
/// getDiagnosticLevel - Based on the way the client configured the Diagnostic
/// object, classify the specified diagnostic ID into a Level, consumable by
diff --git a/lib/Basic/Diagnostic.cpp b/lib/Basic/Diagnostic.cpp
index 31d3b34..21a8aea 100644
--- a/lib/Basic/Diagnostic.cpp
+++ b/lib/Basic/Diagnostic.cpp
@@ -124,10 +124,20 @@
return 0;
}
-bool Diagnostic::isBuiltinSFINAEDiag(unsigned DiagID) {
- if (const StaticDiagInfoRec *Info = GetDiagInfo(DiagID))
- return Info->SFINAE && Info->Class == CLASS_ERROR;
- return false;
+Diagnostic::SFINAEResponse
+Diagnostic::getDiagnosticSFINAEResponse(unsigned DiagID) {
+ if (const StaticDiagInfoRec *Info = GetDiagInfo(DiagID)) {
+ if (!Info->SFINAE)
+ return SFINAE_Report;
+
+ if (Info->Class == CLASS_ERROR)
+ return SFINAE_SubstitutionFailure;
+
+ // Suppress notes, warnings, and extensions;
+ return SFINAE_Suppress;
+ }
+
+ return SFINAE_Report;
}
/// getDiagClass - Return the class field of the diagnostic.
diff --git a/lib/Sema/Sema.cpp b/lib/Sema/Sema.cpp
index 7190cf0..ccfbe1e 100644
--- a/lib/Sema/Sema.cpp
+++ b/lib/Sema/Sema.cpp
@@ -348,6 +348,30 @@
}
}
+Sema::SemaDiagnosticBuilder Sema::Diag(SourceLocation Loc, unsigned DiagID) {
+ if (isSFINAEContext()) {
+ switch (Diagnostic::getDiagnosticSFINAEResponse(DiagID)) {
+ case Diagnostic::SFINAE_Report:
+ // Fall through; we'll report the diagnostic below.
+ break;
+
+ case Diagnostic::SFINAE_SubstitutionFailure:
+ // Count this failure so that we know that template argument deduction
+ // has failed.
+ ++NumSFINAEErrors;
+ // Fall through
+
+ case Diagnostic::SFINAE_Suppress:
+ // Suppress this diagnostic.
+ Diags.setLastDiagnosticIgnored();
+ return SemaDiagnosticBuilder(*this);
+ }
+ }
+
+ DiagnosticBuilder DB = Diags.Report(FullSourceLoc(Loc, SourceMgr), DiagID);
+ return SemaDiagnosticBuilder(DB, *this, DiagID);
+}
+
Sema::SemaDiagnosticBuilder
Sema::Diag(SourceLocation Loc, const PartialDiagnostic& PD) {
SemaDiagnosticBuilder Builder(Diag(Loc, PD.getDiagID()));
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 7e2e614..5986b47 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -610,19 +610,7 @@
};
/// \brief Emit a diagnostic.
- SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID) {
- if (isSFINAEContext() && Diagnostic::isBuiltinSFINAEDiag(DiagID)) {
- // If we encountered an error during template argument
- // deduction, and that error is one of the SFINAE errors,
- // suppress the diagnostic.
- ++NumSFINAEErrors;
- Diags.setLastDiagnosticIgnored();
- return SemaDiagnosticBuilder(*this);
- }
-
- DiagnosticBuilder DB = Diags.Report(FullSourceLoc(Loc, SourceMgr), DiagID);
- return SemaDiagnosticBuilder(DB, *this, DiagID);
- }
+ SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID);
/// \brief Emit a partial diagnostic.
SemaDiagnosticBuilder Diag(SourceLocation Loc, const PartialDiagnostic& PD);