commit a6e8b685e13492abfb2e58dc49007deda165a00d
author Richard Smith <richard-llvm@metafoo.co.uk> Wed Sep 04 20:30:37 2019 +0000
committer Richard Smith <richard-llvm@metafoo.co.uk> Wed Sep 04 20:30:37 2019 +0000
tree 279bbf503976a5c882db2f0699a858d10e66a5e9
parent eca01b031d44da54239d9956ba0acc7cf2f7798b

[c++20] P1143R2: Add support for the C++20 'constinit' keyword.

This is mostly the same as the
[[clang::require_constant_initialization]] attribute, but has a couple
of additional syntactic and semantic restrictions.

In passing, I added a warning for the attribute form being added after
we have already seen the initialization of the variable (but before we
see the definition); that case previously slipped between the cracks and
the attribute was silently ignored.

llvm-svn: 370972

clang/lib/Parse/ParseDecl.cpp

diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index c4c5045..d66c539 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -2514,7 +2514,7 @@
   // Issue diagnostic and remove constexpr specifier if present.
   if (DS.hasConstexprSpecifier() && DSC != DeclSpecContext::DSC_condition) {
     Diag(DS.getConstexprSpecLoc(), diag::err_typename_invalid_constexpr)
-        << (DS.getConstexprSpecifier() == CSK_consteval);
+        << DS.getConstexprSpecifier();
     DS.ClearConstexprSpec();
   }
 }
@@ -3653,15 +3653,16 @@
       isInvalid = DS.setModulePrivateSpec(Loc, PrevSpec, DiagID);
       break;
 
-    // constexpr
+    // constexpr, consteval, constinit specifiers
     case tok::kw_constexpr:
       isInvalid = DS.SetConstexprSpec(CSK_constexpr, Loc, PrevSpec, DiagID);
       break;
-
-    // consteval
     case tok::kw_consteval:
       isInvalid = DS.SetConstexprSpec(CSK_consteval, Loc, PrevSpec, DiagID);
       break;
+    case tok::kw_constinit:
+      isInvalid = DS.SetConstexprSpec(CSK_constinit, Loc, PrevSpec, DiagID);
+      break;
 
     // type-specifier
     case tok::kw_short:
@@ -5080,8 +5081,9 @@
   case tok::annot_decltype:
   case tok::kw_constexpr:
 
-    // C++20 consteval.
+    // C++20 consteval and constinit.
   case tok::kw_consteval:
+  case tok::kw_constinit:
 
     // C11 _Atomic
   case tok::kw__Atomic:

clang/lib/Parse/ParseDeclCXX.cpp

diff --git a/clang/lib/Parse/ParseDeclCXX.cpp b/clang/lib/Parse/ParseDeclCXX.cpp
index cf03ed6..529c09a 100644
--- a/clang/lib/Parse/ParseDeclCXX.cpp
+++ b/clang/lib/Parse/ParseDeclCXX.cpp
@@ -1313,6 +1313,8 @@
   case tok::kw_mutable:         // struct foo {...} mutable   x;
   case tok::kw_thread_local:    // struct foo {...} thread_local x;
   case tok::kw_constexpr:       // struct foo {...} constexpr x;
+  case tok::kw_consteval:       // struct foo {...} consteval x;
+  case tok::kw_constinit:       // struct foo {...} constinit x;
     // As shown above, type qualifiers and storage class specifiers absolutely
     // can occur after class specifiers according to the grammar.  However,
     // almost no one actually writes code like this.  If we see one of these,

clang/lib/Parse/ParseTentative.cpp

diff --git a/clang/lib/Parse/ParseTentative.cpp b/clang/lib/Parse/ParseTentative.cpp
index 8e56e0c..2eee15b 100644
--- a/clang/lib/Parse/ParseTentative.cpp
+++ b/clang/lib/Parse/ParseTentative.cpp
@@ -1408,6 +1408,7 @@
   case tok::kw_typedef:
   case tok::kw_constexpr:
   case tok::kw_consteval:
+  case tok::kw_constinit:
     // storage-class-specifier
   case tok::kw_register:
   case tok::kw_static: