cross compile with my own libc

How do I cross compile (for mips/arm) with my own version of libc using its .a and headers?
I'd like to disable features like exceptions, replace new/delete, no gnu extension etc

Start by reviewing how this project wraps libcxx and how its build configuration handles cross-compilation for MIPS and ARM. Clarify the supported configuration for a custom libc, including supplied .a files and headers, disabled exceptions, custom new/delete, and no GNU extensions; the issue is done when that behavior is documented or supported with a reproducible configuration.

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