diff --git a/gcc/cp/mangle.cc b/gcc/cp/mangle.cc
index 02129c6b89a..3d5e96b2c94 100644
--- a/gcc/cp/mangle.cc
+++ b/gcc/cp/mangle.cc
@@ -1048,6 +1048,12 @@ decl_mangling_context (tree decl)
       tree extra = LAMBDA_TYPE_EXTRA_SCOPE (TREE_TYPE (decl));
       if (extra)
 	return extra;
+      tcontext = CP_DECL_CONTEXT (decl);
+      if (LAMBDA_TYPE_P (tcontext))
+	/* Lambda type context means this lambda appears between the
+	   lambda-introducer and the open brace of another lambda (c++/119175).
+	   That isn't a real scope; look further into the enclosing scope.  */
+	return decl_mangling_context (TYPE_NAME (tcontext));
     }
   else if (template_type_parameter_p (decl))
      /* template type parms have no mangling context.  */
diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-lambda23.C b/gcc/testsuite/g++.dg/cpp2a/concepts-lambda23.C
new file mode 100644
index 00000000000..f44212031dd
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/concepts-lambda23.C
@@ -0,0 +1,12 @@
+// PR c++/119175
+// { dg-do compile { target c++20 } }
+
+template<int = 0>
+static void from() requires requires {
+  []<int> requires requires { [] {}; } {};
+}
+{}
+
+int main() {
+  from();
+}