i have found my bug.
i forgot the RAM offset in the application
STM32F030RCTX_FLASH_APPLICATION.ld (with BUG)
MEMORY
{
RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 32K
FLASH (rx) : ORIGIN = 0x8008000, LENGTH = 256K - 32K
}
STM32F030RCTX_FLASH_APPLICATION.ld (with bugfix)
MEMORY
{
RAM (xrw) : ORIGIN = 0x200000BC, LENGTH = 32K - 0xBC /* The Vector Table in RAM (size = 4x47Byte) must not be used by the application*/
FLASH (rx) : ORIGIN = 0x8008000, LENGTH = 256K - 32K
}
My bare-metal application with the buggy linker-script only worked, because it never called any entry of the vector table.