diff --git a/clang-tools-extra/clang-tidy/llvmlibc/InlineFunctionDeclCheck.cpp b/clang-tools-extra/clang-tidy/llvmlibc/InlineFunctionDeclCheck.cpp
--- a/clang-tools-extra/clang-tidy/llvmlibc/InlineFunctionDeclCheck.cpp
+++ b/clang-tools-extra/clang-tidy/llvmlibc/InlineFunctionDeclCheck.cpp
@@ -39,6 +39,11 @@
                                         HeaderFileExtensions))
     return;
 
+  // Consider only functions with a external and visible declaration.
+  if (auto *MemberDecl = dyn_cast<CXXMethodDecl>(FuncDecl))
+    if (MemberDecl->getParent()->isLambda())
+      return;
+
   // Check if decl starts with LIBC_INLINE
   auto Loc = FullSourceLoc(Result.SourceManager->getFileLoc(SrcBegin),
                            *Result.SourceManager);