[Concepts] Constraint Enforcement & Diagnostics
Part of the C++20 concepts implementation effort.
- Associated constraints (requires clauses, currently) are now enforced when instantiating/specializing templates and when considering partial specializations and function overloads.
- Elaborated diagnostics give helpful insight as to why the constraints were not satisfied.
Phabricator: D41569
Re-commit, after fixing some memory bugs.
diff --git a/clang/lib/Serialization/ASTWriterStmt.cpp b/clang/lib/Serialization/ASTWriterStmt.cpp
index 2b331a97..1e801d0 100644
--- a/clang/lib/Serialization/ASTWriterStmt.cpp
+++ b/clang/lib/Serialization/ASTWriterStmt.cpp
@@ -401,7 +401,25 @@
Record.AddASTTemplateArgumentListInfo(E->getTemplateArgsAsWritten());
for (const TemplateArgument &Arg : TemplateArgs)
Record.AddTemplateArgument(Arg);
- Record.push_back(E->isSatisfied());
+ const ASTConstraintSatisfaction &Satisfaction = E->getSatisfaction();
+ Record.push_back(Satisfaction.IsSatisfied);
+ if (!Satisfaction.IsSatisfied) {
+ Record.push_back(Satisfaction.NumRecords);
+ for (const auto &DetailRecord : Satisfaction) {
+ Record.AddStmt(const_cast<Expr *>(DetailRecord.first));
+ auto *E = DetailRecord.second.dyn_cast<Expr *>();
+ Record.push_back(E == nullptr);
+ if (E)
+ Record.AddStmt(E);
+ else {
+ auto *Diag = DetailRecord.second.get<std::pair<SourceLocation,
+ StringRef> *>();
+ Record.AddSourceLocation(Diag->first);
+ Record.AddString(Diag->second);
+ }
+ }
+ }
+
Code = serialization::EXPR_CONCEPT_SPECIALIZATION;
}