Can't cross-compile to Windows with module_mbedtls_enabled=no

[kus04e4ek]

Tested versions

43b32f9 (latest)

• Introduced by mbedTLS: Update to new LTS v3.6.0 #90482

System information

Linux

Issue description

When I cross-compile from Linux to Windows using module_mbedtls_enabled=no, I get the following errors:

In file included from thirdparty/mbedtls/include/mbedtls/build_info.h:174,
                 from thirdparty/mbedtls/library/common.h:14,
                 from thirdparty/mbedtls/library/aes.c:14:
thirdparty/mbedtls/include/mbedtls/check_config.h:28:2: error: #error "MBEDTLS_PLATFORM_C is required on Windows"
   28 | #error "MBEDTLS_PLATFORM_C is required on Windows"
      |  ^~~~~
In file included from thirdparty/mbedtls/include/mbedtls/build_info.h:174,
                 from thirdparty/mbedtls/library/common.h:14,
                 from thirdparty/mbedtls/library/aes.c:14:
thirdparty/mbedtls/include/mbedtls/check_config.h:578:2: error: #error "MBEDTLS_PLATFORM_SNPRINTF_ALT defined, but not all prerequisites"
  578 | #error "MBEDTLS_PLATFORM_SNPRINTF_ALT defined, but not all prerequisites"
      |  ^~~~~
thirdparty/mbedtls/include/mbedtls/check_config.h:592:2: error: #error "MBEDTLS_PLATFORM_VSNPRINTF_ALT defined, but not all prerequisites"
  592 | #error "MBEDTLS_PLATFORM_VSNPRINTF_ALT defined, but not all prerequisites"
      |  ^~~~~

Just compiling to Linux doesn't produce any errors.
This diff seems to fix it partially, though I get linker errors with undefined references:

diff --git a/thirdparty/mbedtls/include/godot_core_mbedtls_config.h b/thirdparty/mbedtls/include/godot_core_mbedtls_config.h
index d27bf608fbe..e65f332849f 100644
--- a/thirdparty/mbedtls/include/godot_core_mbedtls_config.h
+++ b/thirdparty/mbedtls/include/godot_core_mbedtls_config.h
@@ -33,6 +33,9 @@
 
 #include <limits.h>
 
+// Include default mbedTLS config.
+#include <mbedtls/mbedtls_config.h>
+
 // For AES
 #define MBEDTLS_CIPHER_MODE_CBC
 #define MBEDTLS_CIPHER_MODE_CFB

Copied from:

godot/thirdparty/mbedtls/include/godot_module_mbedtls_config.h

Lines 43 to 44 in 578d937

	// Include default mbedTLS config.
	#include <mbedtls/mbedtls_config.h>

Cross-compiling is probably unrelated to this, but I can't test it on Windows and thought it would be better to mention it.

Steps to reproduce

Compile to Windows using module_mbedtls_enabled=no

[Faless]

Just tested building Windows with VS 2019 MSVC and module_mbedtls_enabled=no and I get no error.

So it might be a mingw specific path, I'll try cross compiling from linux now.

[Faless]

I confirm I get the same error with MinGW/LLVM from Linux, will investigate, we might be missing some new define in our core config.

[Faless]

And this is why it works on VS 2019 (_MSC_VER > 1900), so the issue also affects VS 2017 (which AFAIU is the minimal supported version to build Godot) (EDIT: _MSC_VER <= 1900 only for VS <= 2015, so it's not an issue with supported MSVC versions, only MinGW):

godot/thirdparty/mbedtls/include/mbedtls/check_config.h

Lines 26 to 32 in c951421

	#if defined(__MINGW32__) || (defined(_MSC_VER) && _MSC_VER <= 1900)
	#if !defined(MBEDTLS_PLATFORM_C)
	#error "MBEDTLS_PLATFORM_C is required on Windows"
	#endif
	/* See auto-enabling SNPRINTF_ALT and VSNPRINTF_ALT
	* in * config_adjust_legacy_crypto.h */
	#endif /* _MINGW32__ || (_MSC_VER && (_MSC_VER <= 1900)) */