From: Conor Dooley conor.dooley@microchip.com
commit 33549fcf37ec461f398f0a41e1c9948be2e5aca4 upstream
During the discussion before supporting rust on riscv, it was decided not to support gcc yet, due to differences in extension handling compared to llvm (only the version of libclang matching the c compiler is supported). Recently Jason Montleon reported [1] that building with gcc caused build issues, due to unsupported arguments being passed to libclang. After some discussion between myself and Miguel, it is better to disable gcc + rust builds to match the original intent, and subsequently support it when an appropriate set of extensions can be deduced from the version of libclang.
Closes: https://lore.kernel.org/all/20240917000848.720765-2-jmontleo@redhat.com/ [1] Link: https://lore.kernel.org/all/20240926-battering-revolt-6c6a7827413e@spud/ [2] Fixes: 70a57b247251a ("RISC-V: enable building 64-bit kernels with rust support") Cc: stable@vger.kernel.org Reported-by: Jason Montleon jmontleo@redhat.com Signed-off-by: Conor Dooley conor.dooley@microchip.com Acked-by: Miguel Ojeda ojeda@kernel.org Reviewed-by: Nathan Chancellor nathan@kernel.org Link: https://lore.kernel.org/r/20241001-playlist-deceiving-16ece2f440f5@spud Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Conor Dooley conor.dooley@microchip.com --- Documentation/rust/arch-support.rst | 2 +- arch/riscv/Kconfig | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/rust/arch-support.rst b/Documentation/rust/arch-support.rst index 750ff371570a..54be7ddf3e57 100644 --- a/Documentation/rust/arch-support.rst +++ b/Documentation/rust/arch-support.rst @@ -17,7 +17,7 @@ Architecture Level of support Constraints ============= ================ ============================================== ``arm64`` Maintained Little Endian only. ``loongarch`` Maintained - -``riscv`` Maintained ``riscv64`` only. +``riscv`` Maintained ``riscv64`` and LLVM/Clang only. ``um`` Maintained - ``x86`` Maintained ``x86_64`` only. ============= ================ ============================================== diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index d11c2479d8e1..6651a5cbdc27 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -172,7 +172,7 @@ config RISCV select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RETHOOK if !XIP_KERNEL select HAVE_RSEQ - select HAVE_RUST if 64BIT + select HAVE_RUST if 64BIT && CC_IS_CLANG select HAVE_SAMPLE_FTRACE_DIRECT select HAVE_SAMPLE_FTRACE_DIRECT_MULTI select HAVE_STACKPROTECTOR