[llvm] [Support][NFC] Avoid weak vtable warning for JSON ParseError (PR #182511)

[Alexis Engelke via llvm-commits]

https://github.com/aengelke updated https://github.com/llvm/llvm-project/pull/182511

>From 37f97cea2df6e1f783732ff63ae0420eca5bfa75 Mon Sep 17 00:00:00 2001
From: Alexis Engelke <engelke at in.tum.de>
Date: Fri, 20 Feb 2026 15:17:28 +0000
Subject: [PATCH 1/2] [Support][NFC] Avoid weak vtable for JSON ParseError

---
 llvm/include/llvm/Support/JSON.h | 4 +---
 llvm/lib/Support/JSON.cpp        | 5 +++++
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/llvm/include/llvm/Support/JSON.h b/llvm/include/llvm/Support/JSON.h
index ad4f891f99bb7..27862eb7ab6bb 100644
--- a/llvm/include/llvm/Support/JSON.h
+++ b/llvm/include/llvm/Support/JSON.h
@@ -918,9 +918,7 @@ class ParseError : public llvm::ErrorInfo<ParseError> {
   LLVM_ABI static char ID;
   ParseError(const char *Msg, unsigned Line, unsigned Column, unsigned Offset)
       : Msg(Msg), Line(Line), Column(Column), Offset(Offset) {}
-  void log(llvm::raw_ostream &OS) const override {
-    OS << llvm::formatv("[{0}:{1}, byte={2}]: {3}", Line, Column, Offset, Msg);
-  }
+  void log(llvm::raw_ostream &OS) const override;
   std::error_code convertToErrorCode() const override {
     return llvm::inconvertibleErrorCode();
   }
diff --git a/llvm/lib/Support/JSON.cpp b/llvm/lib/Support/JSON.cpp
index e9fd8f8fae1fa..33901a96d0ec5 100644
--- a/llvm/lib/Support/JSON.cpp
+++ b/llvm/lib/Support/JSON.cpp
@@ -688,8 +688,13 @@ Expected<Value> parse(StringRef JSON) {
         return std::move(E);
   return P.takeError();
 }
+
 char ParseError::ID = 0;
 
+void ParseError::log(llvm::raw_ostream &OS) const {
+  OS << llvm::formatv("[{0}:{1}, byte={2}]: {3}", Line, Column, Offset, Msg);
+}
+
 bool isUTF8(llvm::StringRef S, size_t *ErrOffset) {
   // Fast-path for ASCII, which is valid UTF-8.
   if (LLVM_LIKELY(isASCII(S)))

>From 55558f1d06d4b3cf63386cb7a70c12ed25ba15ab Mon Sep 17 00:00:00 2001
From: Alexis Engelke <engelke at in.tum.de>
Date: Fri, 20 Feb 2026 15:25:23 +0000
Subject: [PATCH 2/2] add comment

---
 llvm/lib/Support/JSON.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/llvm/lib/Support/JSON.cpp b/llvm/lib/Support/JSON.cpp
index 33901a96d0ec5..547e721b4ad64 100644
--- a/llvm/lib/Support/JSON.cpp
+++ b/llvm/lib/Support/JSON.cpp
@@ -691,6 +691,7 @@ Expected<Value> parse(StringRef JSON) {
 
 char ParseError::ID = 0;
 
+// Defined out-of-line to place vtable in this compilation unit.
 void ParseError::log(llvm::raw_ostream &OS) const {
   OS << llvm::formatv("[{0}:{1}, byte={2}]: {3}", Line, Column, Offset, Msg);
 }