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The upstream release page can be found here.

RISC-V status

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• RV32GC = RV32IMAFDC is implemented
• RV64GC = RV64IMAFDC is implemented
• RV32E is not supported
• Some non-ratified extensions have been merged mainline (they need the flag -menable-experimental-extensions to enable them):
  • Bitmanip v0.93
    • b, zba, zbb, zbc, zbe, zbf, zbm, zbp, zbr, zbs, zbt, zbproposedc
  • Vector v0.10
    • z, zvamo, zvlsseg
    • Example command for building: clang --target=riscv64-unknown-elf -march=rv64gcv0p10 -menable-experimental-extensions 
  • Floating-point v0.1
    • zfh
• LLVM supports -msave-restore
• RISC-V specific command-line options: https://clang.llvm.org/docs/ClangCommandLineReference.html#riscv

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Newlib

Newlib is a C standard library implementation intended for use on embedded systems.

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