[clang] [clang] Remove an incorrect assertion in ConstantFoldAttrs (PR #105789)

[Timm Baeder via cfe-commits]

https://github.com/tbaederr updated https://github.com/llvm/llvm-project/pull/105789

>From 62c8614cd64e0b97b62eb5700ff39dd290bbeebf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timm=20B=C3=A4der?= <tbaeder at redhat.com>
Date: Fri, 23 Aug 2024 08:54:12 +0200
Subject: [PATCH] [clang] Remove an incorrect assertion in ConstantFoldAttrs

Evaluating the attribute expression can be successful without resulting
in a value. Namely, when the expression is of type void.
---
 clang/lib/Sema/SemaAttr.cpp              |  1 -
 clang/test/CodeGenCXX/attr-annotate2.cpp | 10 ++++++++++
 clang/test/SemaCXX/attr-annotate.cpp     |  4 ++++
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/clang/lib/Sema/SemaAttr.cpp b/clang/lib/Sema/SemaAttr.cpp
index 6907fa91e28c20..defdda17c32ded 100644
--- a/clang/lib/Sema/SemaAttr.cpp
+++ b/clang/lib/Sema/SemaAttr.cpp
@@ -537,7 +537,6 @@ bool Sema::ConstantFoldAttrArgs(const AttributeCommonInfo &CI,
         Diag(Note.first, Note.second);
       return false;
     }
-    assert(Eval.Val.hasValue());
     E = ConstantExpr::Create(Context, E, Eval.Val);
   }
 
diff --git a/clang/test/CodeGenCXX/attr-annotate2.cpp b/clang/test/CodeGenCXX/attr-annotate2.cpp
index 1c9c39c9efb83b..0b57af1b42a05a 100644
--- a/clang/test/CodeGenCXX/attr-annotate2.cpp
+++ b/clang/test/CodeGenCXX/attr-annotate2.cpp
@@ -4,18 +4,28 @@
 // CHECK: @[[STR:.*]] = private unnamed_addr constant [45 x i8] c"_Generic selection expression should be fine\00", section "llvm.metadata"
 // CHECK-NEXT: @[[FILENAME:.*]] = private unnamed_addr constant {{.*}}, section "llvm.metadata"
 // CHECK-NEXT: @[[ARGS:.*]] = private unnamed_addr constant { i32 } zeroinitializer, section "llvm.metadata"
+// CHECK-NEXT: @[[STR2:.*]] = private unnamed_addr constant [14 x i8] c"void is undef\00", section "llvm.metadata"
+// CHECK-NEXT: @[[ARGS3:.*]] = private unnamed_addr constant { i8, i8, i32 } { i8 undef, i8 undef, i32 7 }, section "llvm.metadata"
+
+
 
 // CHECK-LABEL: @_Z1fv(
 // CHECK-NEXT:  entry:
 // CHECK-NEXT:    [[N:%.*]] = alloca i32, align 4
 // CHECK-NEXT:    [[J:%.*]] = alloca i32, align 4
+// CHECK-NEXT:    [[K:%.*]] = alloca i32, align 4
 // CHECK-NEXT:    store i32 10, ptr [[N]], align 4
 // CHECK-NEXT:    call void @llvm.var.annotation.p0.p0(ptr [[J]], ptr @[[STR]], ptr @[[FILENAME]], i32 {{.*}}, ptr @[[ARGS]])
 // CHECK-NEXT:    store i32 0, ptr [[J]], align 4
+// CHECK-NEXT:    call void @llvm.var.annotation.p0.p0(ptr [[K]], ptr @[[STR2]], ptr @[[FILENAME]], i32 {{.*}}, ptr @[[ARGS3]])
+// CHECK-NEXT:    store i32 0, ptr [[K]], align 4
 // CHECK-NEXT:    ret void
 //
 void f() {
   int n = 10;
   [[clang::annotate("_Generic selection expression should be fine", _Generic(n, int : 0, default : 1))]]
   int j = 0; // second arg should resolve to 0 fine
+
+  [[clang::annotate("void is undef", (void)2, (void)4, 7)]]
+  int k = 0;
 }
diff --git a/clang/test/SemaCXX/attr-annotate.cpp b/clang/test/SemaCXX/attr-annotate.cpp
index 846ef4119f1d7c..ff538fee9cb3c7 100644
--- a/clang/test/SemaCXX/attr-annotate.cpp
+++ b/clang/test/SemaCXX/attr-annotate.cpp
@@ -134,3 +134,7 @@ constexpr int foldable_but_invalid() {
 template <typename T> [[clang::annotate()]] void f2() {}
 // expected-error at -1 {{'annotate' attribute takes at least 1 argument}}
 }
+
+namespace test5 {
+  void bir [[clang::annotate("B", (void)1)]] ();
+}