[clang] [WIP][clang] use getDeclName in static assert failed boolean condition printer (PR #203736)

[Fan Mo via cfe-commits]

https://github.com/w007878 updated https://github.com/llvm/llvm-project/pull/203736

>From c5bf40cb6076c5a20bad7eb7997844236b360545 Mon Sep 17 00:00:00 2001
From: Fan Mo <w007878 at hotmail.com>
Date: Sat, 13 Jun 2026 20:33:20 -0500
Subject: [PATCH 1/2] fix: use getDeclName in static assert failed boolean
 condition printer

---
 clang/lib/Sema/SemaTemplate.cpp      |  2 +-
 clang/test/SemaCXX/static-assert.cpp | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 8c94a1ad39208..41664f36dd6a3 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -3647,7 +3647,7 @@ class FailedBooleanConditionPrinterHelper : public PrinterHelper {
       DR->getQualifier().print(OS, Policy, true);
       // Then print the decl itself.
       const ValueDecl *VD = DR->getDecl();
-      OS << VD->getName();
+      OS << VD->getDeclName();
       if (const auto *IV = dyn_cast<VarTemplateSpecializationDecl>(VD)) {
         // This is a template variable, print the expanded template arguments.
         printTemplateArgumentList(
diff --git a/clang/test/SemaCXX/static-assert.cpp b/clang/test/SemaCXX/static-assert.cpp
index 354016db36432..f9c6378ecc396 100644
--- a/clang/test/SemaCXX/static-assert.cpp
+++ b/clang/test/SemaCXX/static-assert.cpp
@@ -364,3 +364,17 @@ namespace Diagnostics {
   static_assert(1 << 3 != 8, ""); // expected-error {{failed}} \
                                  // expected-note {{evaluates to '8 != 8'}}
 }
+
+namespace GH203701 {
+  struct S {
+    constexpr S(auto) {}
+    constexpr operator int() const { return 0; }
+    constexpr static f() const { return 0; }
+  };
+
+  constexpr auto a = [](this S) { return 1; };
+
+  static_assert((&decltype(a)::operator())(1) == 42); // expected-error {{static assertion failed}}
+  static_assert((&S::operator int) == nullptr, ""); // expected-error {{static assertion failed}}
+  static_assert((S::f() == 1)); // expected-error {{static assertion failed}}
+}

>From 66e68710b4a2e4e220d45a54f18a891a52abe595 Mon Sep 17 00:00:00 2001
From: Fan Mo <w007878 at hotmail.com>
Date: Sat, 13 Jun 2026 21:42:16 -0500
Subject: [PATCH 2/2] fix test

---
 clang/test/SemaCXX/static-assert.cpp | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/clang/test/SemaCXX/static-assert.cpp b/clang/test/SemaCXX/static-assert.cpp
index f9c6378ecc396..21a11ee7a5c45 100644
--- a/clang/test/SemaCXX/static-assert.cpp
+++ b/clang/test/SemaCXX/static-assert.cpp
@@ -369,12 +369,10 @@ namespace GH203701 {
   struct S {
     constexpr S(auto) {}
     constexpr operator int() const { return 0; }
-    constexpr static f() const { return 0; }
   };
 
   constexpr auto a = [](this S) { return 1; };
 
-  static_assert((&decltype(a)::operator())(1) == 42); // expected-error {{static assertion failed}}
-  static_assert((&S::operator int) == nullptr, ""); // expected-error {{static assertion failed}}
-  static_assert((S::f() == 1)); // expected-error {{static assertion failed}}
+  static_assert((&decltype(a)::operator())(1) == 42, ""); // expected-error-re {{static assertion failed due to requirement '(&const GH203701::(lambda at {.*})::operator())(1) == 42'}}
+  static_assert((&S::operator int) == nullptr, ""); // expected-error {{static assertion failed due to requirement '(&GH203701::S::operator int) == nullptr'}}
 }