Remove awful Mingw32 workarounds

Instead a warning is triggered if an affected compiler is detected.
closes #12022

3 files changed, 10 insertions, 34 deletions

diff --git a/src/main.cpp b/src/main.cpp
index ca95ef874..5ea212d8a 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -65,6 +65,14 @@ extern "C" {
 #error Minetest cannot be built without exceptions or RTTI
 #endif
 
+#if defined(__MINGW32__) && !defined(__MINGW64__) && !defined(__clang__) && \
+	(__GNUC__ < 11 || (__GNUC__ == 11 && __GNUC_MINOR__ < 1))
+// see e.g. https://github.com/minetest/minetest/issues/10137
+#warning ==================================
+#warning 32-bit MinGW gcc before 11.1 has known issues with crashes on thread exit, you should upgrade.
+#warning ==================================
+#endif
+
 #define DEBUGFILE "debug.txt"
 #define DEFAULT_SERVER_PORT 30000
 
diff --git a/src/script/common/c_converter.cpp b/src/script/common/c_converter.cpp
index 716405593..08fb9ad30 100644
--- a/src/script/common/c_converter.cpp
+++ b/src/script/common/c_converter.cpp
@@ -452,17 +452,9 @@ size_t read_stringlist(lua_State *L, int index, std::vector<std::string> *result
 	Table field getters
 */
 
-#if defined(__MINGW32__) && !defined(__MINGW64__)
-/* MinGW 32-bit somehow crashes in the std::set destructor when this
- * variable is thread-local, so just don't do that. */
-static std::set<u64> warned_msgs;
-#endif
-
 bool check_field_or_nil(lua_State *L, int index, int type, const char *fieldname)
 {
-#if !defined(__MINGW32__) || defined(__MINGW64__)
 	thread_local std::set<u64> warned_msgs;
-#endif
 
 	int t = lua_type(L, index);
 	if (t == LUA_TNIL)
diff --git a/src/serialization.cpp b/src/serialization.cpp
index d4d7b5f6e..d3009bc83 100644
--- a/src/serialization.cpp
+++ b/src/serialization.cpp
@@ -208,30 +208,11 @@ struct ZSTD_Deleter {
 	}
 };
 
-#if defined(__MINGW32__) && !defined(__MINGW64__)
-/*
- * This is exactly as dumb as it looks.
- * Yes, this is a memory leak. No, we don't have better solution right now.
- */
-template<typename T> class leaky_ptr
-{
-	T *value;
-public:
-	leaky_ptr(T *value) : value(value) {};
-	T *get() { return value; }
-};
-#endif
-
 void compressZstd(const u8 *data, size_t data_size, std::ostream &os, int level)
 {
-#if defined(__MINGW32__) && !defined(__MINGW64__)
-	// leaks one context per thread but doesn't crash :shrug:
-	thread_local leaky_ptr<ZSTD_CStream> stream(ZSTD_createCStream());
-#else
 	// reusing the context is recommended for performance
-	// it will destroyed when the thread ends
+	// it will be destroyed when the thread ends
 	thread_local std::unique_ptr<ZSTD_CStream, ZSTD_Deleter> stream(ZSTD_createCStream());
-#endif
 
 
 	ZSTD_initCStream(stream.get(), level);
@@ -276,14 +257,9 @@ void compressZstd(const std::string &data, std::ostream &os, int level)
 
 void decompressZstd(std::istream &is, std::ostream &os)
 {
-#if defined(__MINGW32__) && !defined(__MINGW64__)
-	// leaks one context per thread but doesn't crash :shrug:
-	thread_local leaky_ptr<ZSTD_DStream> stream(ZSTD_createDStream());
-#else
 	// reusing the context is recommended for performance
-	// it will destroyed when the thread ends
+	// it will be destroyed when the thread ends
 	thread_local std::unique_ptr<ZSTD_DStream, ZSTD_Deleter> stream(ZSTD_createDStream());
-#endif
 
 	ZSTD_initDStream(stream.get());