diff --git a/docs/mkdocs/docs/api/macros/json_no_thread_local.md b/docs/mkdocs/docs/api/macros/json_no_thread_local.md
index d98745243..126116ec3 100644
--- a/docs/mkdocs/docs/api/macros/json_no_thread_local.md
+++ b/docs/mkdocs/docs/api/macros/json_no_thread_local.md
@@ -26,6 +26,9 @@ By default, `#!cpp JSON_NO_THREAD_LOCAL` is not defined.
 #undef JSON_NO_THREAD_LOCAL
 ```
 
+The library defines it by itself for Clang targeting MinGW, which does not survive the `#!cpp thread_local` storage:
+copying a value segfaults there, with both old and current Clang versions, while GCC targeting MinGW is unaffected.
+
 ## Examples
 
 ??? example
diff --git a/include/nlohmann/detail/macro_scope.hpp b/include/nlohmann/detail/macro_scope.hpp
index 4682fd361..e096fcb62 100644
--- a/include/nlohmann/detail/macro_scope.hpp
+++ b/include/nlohmann/detail/macro_scope.hpp
@@ -186,6 +186,15 @@
     #define JSON_NO_UNIQUE_ADDRESS
 #endif
 
+// Clang targeting MinGW does not survive the thread_local storage the copy
+// constructor uses to bound its descent: every test that copies a value
+// segfaults with clang 11.0.1 and clang 18.1.8, while the same tests pass with
+// GCC targeting MinGW and with every other toolchain the library is tested on.
+// Copying works the same way without the counter, only more slowly.
+#if !defined(JSON_NO_THREAD_LOCAL) && defined(__clang__) && defined(__MINGW32__)
+    #define JSON_NO_THREAD_LOCAL 1
+#endif
+
 // disable documentation warnings on clang
 #if defined(__clang__)
     #pragma clang diagnostic push
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index 4ab4e4a92..192b0ad06 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -2561,6 +2561,15 @@ JSON_HEDLEY_DIAGNOSTIC_POP
     #define JSON_NO_UNIQUE_ADDRESS
 #endif
 
+// Clang targeting MinGW does not survive the thread_local storage the copy
+// constructor uses to bound its descent: every test that copies a value
+// segfaults with clang 11.0.1 and clang 18.1.8, while the same tests pass with
+// GCC targeting MinGW and with every other toolchain the library is tested on.
+// Copying works the same way without the counter, only more slowly.
+#if !defined(JSON_NO_THREAD_LOCAL) && defined(__clang__) && defined(__MINGW32__)
+    #define JSON_NO_THREAD_LOCAL 1
+#endif
+
 // disable documentation warnings on clang
 #if defined(__clang__)
     #pragma clang diagnostic push