I 've a module with a Cortex-M4 Vybrid VF61 processor and an installed linux.
The installed linux does not provide gcc and gdb for native compiling and debugging.
Please, can anybody tell me, where I can download a prebuilt gcc and a prebuilt gdb for native compiling and debugging ?
Please try here: https://developer.arm.com/open-source/gnu-toolchain/gnu-rm
You will find here embedded toolchains which allow you to cross compile your programs to e.g. Cortex-M4 boards.
Running natively gcc and gdb on Cortex-M4 board might be tricky as not many support e.g. Linux as its host operating system.
For embedded systems you would rather use JTAG interface (or similar) to debug your embedded / bare-metal host using GDB. GDB would be running on your PC/Mac and via JTAG you would connect to your board to flash firmware and debug.