Yes, it is valid. Consider for example: If you are an embedded hardware company. You modify GCC to support a new target / platform. Then, you can compile C code and create binaries for your embedded hardware.
As long as GCC is not distributed, this is a perfectly valid use case for GPL'd software.
Less abstract: Facebook famously has massive internal patches for MySQL, which is GPL'd. And of course, Google has massive internal patches for Linux kernel, which is also GPL'd.
As long as GCC is not distributed, this is a perfectly valid use case for GPL'd software.
Less abstract: Facebook famously has massive internal patches for MySQL, which is GPL'd. And of course, Google has massive internal patches for Linux kernel, which is also GPL'd.