cmake: zephyr: Define LLVM_USE_LLD for the llvm variant - #1162
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The llvm toolchain description hardcodes 'set(LINKER lld)' in cmake/zephyr/llvm/generic.cmake, but nothing ever told Kconfig about it. Zephyr's linker scripts wrap the output section descriptions for .symtab, .strtab and .shstrtab in '#if defined(CONFIG_LLVM_USE_LLD)', because lld models these as synthetic input sections that have to be placed by the linker script, while GNU ld creates them internally after script processing. That symbol is declared only in Zephyr's cmake/toolchain/host/llvm/Kconfig, which is not sourced for the 'zephyr' variant. CONFIG_LLVM_USE_LLD was therefore never set with ZEPHYR_TOOLCHAIN_VARIANT set to zephyr/llvm, and every link reported the sections as orphans: ld.lld: warning: <internal>:(.symtab) is being placed in '.symtab' ld.lld: warning: <internal>:(.shstrtab) is being placed in '.shstrtab' ld.lld: warning: <internal>:(.strtab) is being placed in '.strtab' Define the symbol in the SDK's Kconfig. No choice is needed, as lld is the only linker this variant can use. Assisted-by: Claude:opus-5 Signed-off-by: Tim Pambor <tim.pambor@codewrights.de>
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The llvm toolchain description hardcodes
set(LINKER lld)incmake/zephyr/llvm/generic.cmake, but nothing ever told Kconfig about it.Zephyr's linker scripts wrap the output section descriptions for
.symtab,.strtaband.shstrtabin#if defined(CONFIG_LLVM_USE_LLD), because lld models these as synthetic input sections that have to be placed by the linker script, while GNU ld creates them internally after script processing. That symbol is declared only in Zephyr'scmake/toolchain/host/llvm/Kconfig, which is not sourced for thezephyr/llvmvariant.CONFIG_LLVM_USE_LLDwas therefore never set withZEPHYR_TOOLCHAIN_VARIANTset tozephyr/llvm, and every link reported the sections as orphans:Define the symbol in the SDK's Kconfig. No choice is needed, as lld is the only linker this variant can use.
Fixes zephyrproject-rtos/zephyr#96389