[clang] c7b400f - [clang][Interp] Fix ignoring SubstNonTypeTemplateParmExpr

[Timm Bäder via cfe-commits]

Author: Timm Bäder
Date: 2023-08-01T10:25:16+02:00
New Revision: c7b400f4a8d6a0230f8479945820652b37db4d66

URL: https://github.com/llvm/llvm-project/commit/c7b400f4a8d6a0230f8479945820652b37db4d66
DIFF: https://github.com/llvm/llvm-project/commit/c7b400f4a8d6a0230f8479945820652b37db4d66.diff

LOG: [clang][Interp] Fix ignoring SubstNonTypeTemplateParmExpr

Ignore the expressions and re-do the tests without all the "result
ignored" expected warnings. Those are expected, given the nature of the
tests.

Differential Revision: https://reviews.llvm.org/D149831

Added: 
    

Modified: 
    clang/lib/AST/Interp/ByteCodeExprGen.cpp
    clang/test/AST/Interp/literals.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/AST/Interp/ByteCodeExprGen.cpp b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
index 39dd42655436da..1508b0619a19ad 100644
--- a/clang/lib/AST/Interp/ByteCodeExprGen.cpp
+++ b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
@@ -476,6 +476,8 @@ bool ByteCodeExprGen<Emitter>::VisitInitListExpr(const InitListExpr *E) {
 template <class Emitter>
 bool ByteCodeExprGen<Emitter>::VisitSubstNonTypeTemplateParmExpr(
     const SubstNonTypeTemplateParmExpr *E) {
+  if (DiscardResult)
+    return this->discard(E->getReplacement());
   return this->visit(E->getReplacement());
 }
 

diff  --git a/clang/test/AST/Interp/literals.cpp b/clang/test/AST/Interp/literals.cpp
index 6610770a884e21..9f31cd909e2938 100644
--- a/clang/test/AST/Interp/literals.cpp
+++ b/clang/test/AST/Interp/literals.cpp
@@ -876,51 +876,62 @@ constexpr int ignoredDecls() {
 }
 static_assert(ignoredDecls() == 12, "");
 
-struct A{ int a; };
-constexpr int ignoredExprs() {
-  (void)(1 / 2);
-  A a;
-  a; // expected-warning {{unused}} \
-     // ref-warning {{unused}}
-  (void)a;
-  (a); // expected-warning {{unused}} \
-       // ref-warning {{unused}}
-
-  (void)5, (void)6;
-
-  1 ? 0 : 1; // expected-warning {{unused}} \
-             // ref-warning {{unused}}
-  /// Ignored MaterializeTemporaryExpr.
-  struct B{ const int &a; };
-  (void)B{12};
-  return 0;
-}
+namespace DiscardExprs {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-value"
+
+  struct A{ int a; };
+  constexpr int ignoredExprs() {
+    (void)(1 / 2);
+    A a;
+    a;
+    (void)a;
+    (a);
+
+    /// Ignored MaterializeTemporaryExpr.
+    struct B{ const int &a; };
+    (void)B{12};
+
+    (void)5, (void)6;
 
-/// Ignored comma expressions still have their
-/// expressions evaluated.
-constexpr int Comma(int start) {
-    int i = start;
+    1 ? 0 : 1;
+    return 0;
+  }
+
+  /// Ignored comma expressions still have their
+  /// expressions evaluated.
+  constexpr int Comma(int start) {
+      int i = start;
 
-    (void)i++;
-    (void)i++,(void)i++;
+      (void)i++;
+      (void)i++,(void)i++;
+      return i;
+  }
+  constexpr int Value = Comma(5);
+  static_assert(Value == 8, "");
+
+  /// Ignored MemberExprs need to still evaluate the Base
+  /// expr.
+  constexpr A callme(int &i) {
+    ++i;
+    return A{};
+  }
+  constexpr int ignoredMemberExpr() {
+    int i = 0;
+    callme(i).a;
     return i;
+  }
+  static_assert(ignoredMemberExpr() == 1, "");
+
+  template <int I>
+  constexpr int foo() {
+    I;
+    return I;
+  }
+  static_assert(foo<3>() == 3, "");
+
+#pragma clang diagnostic pop
 }
-constexpr int Value = Comma(5);
-static_assert(Value == 8, "");
-
-/// Ignored MemberExprs need to still evaluate the Base
-/// expr.
-constexpr A callme(int &i) {
-  ++i;
-  return A{};
-}
-constexpr int ignoredMemberExpr() {
-  int i = 0;
-  callme(i).a; // ref-warning {{result unused}} \
-               // expected-warning {{result unused}}
-  return i;
-}
-static_assert(ignoredMemberExpr() == 1, "");
 #endif
 
 namespace PredefinedExprs {