STM32 are one of the most popular Cortex ARM devices on the market as they are with aggresive pricing and nice features. The semiconductor crisis hit ST as all other semiconductor vendors and STM32 disappeared from the market. Many customers have been left for more than year without MCus.
GigaDevices is well known Flash memory manufacturer, they have range of ARM Cortex M3, M4 devices which are pin to pin compatible with STM32 MCUs.
We check GD32 assembled on our STM32 boards and they work equal the only difference we notice is that GD32 lack two wires JTAG SWD interface and only support the full JTAG, which is not big issue.
All code we test run equal on both STM32 and GD32.
Here are links for the GigaDevices based boards:
GD32-H103 header board equal to STM32-H103
GD32-P103 prototype board equal to STM32-P103
OLIMEXINO-GD32 Arduino like board equal to OLIMEXINO-STM32
OLIMEXINO-GD32F3 Arduino like board equal to OLIMEXINO-STM32F3
GD32-H405 header board equal to STM32-H405
GD32-P405 prototype board equal to STM32-P405
GD32-H407 development board equal to STM32-H407
GD32-E407 development board equal to STM32-E407
GD32-P407 development board equal to STM32-P407
olimex 
Jul 23, 2022 @ 02:59:42
Still wondering why more and more Chinese semiconductors are well available on the market and western semiconductors are not even available in homeopathic doses…
Aug 06, 2022 @ 21:58:40
In my opinion it is a type of cold war.
Aug 15, 2022 @ 16:59:05
GD32 MCU Dfu Tool 3.8. 2.9056 Introduction: This programming software based on the bootloader in the GD32 RISC-V chip, the communication interface supports USB, and supports the basic operations of programming / erasing / reading MCU flash and ob.
Aug 19, 2022 @ 22:08:55
Looking for help getting the GD32 into DFU.