Hi Tom,
On 5/5/26 5:10 PM, Tom Rini wrote:
On Tue, May 05, 2026 at 01:58:26PM +0200, Quentin Schulz wrote:
Hi Tom,
On 5/4/26 8:04 PM, Tom Rini wrote:
On Mon, May 04, 2026 at 03:20:27PM +0200, Quentin Schulz wrote:
[...]
The first two patches are for fixing pytest calling make directly on a
"dirty" build directory as generated by buildman using the clang-20
toolchain, but pytest does not set HOSTCC and CC to clang-20, resulting
in clang flags being used with gcc).
One can simply reproduce it (after backporting up to patch
"scripts/Makefile.extrawarn: sync with 6.1") by doing so in the
container:
make HOSTCC=clang-20 CC=clang-20 O=build/sandbox sandbox_defconfig
make HOSTCC=clang-20 CC=clang-20 O=build/sandbox -j`nproc
make O=build/sandbox u-boot-initial-env
It'll print:
gcc: error: unrecognized command-line option '-mno-global-merge'
gcc: error: unrecognized command-line option '-Wformat-invalid-specifier'
gcc: error: unrecognized command-line option '-Qunused-arguments'
This is essentially what's run within test_env_initial_env_file in
test/py/tests/test_env.py.
While I'm not unhappy with the patches to pytest, it feels to me we may
be missing something else for the u-boot-initial-env make target to
update the kconfig symbol based on the toolchain being used when called.
Is there some other target in the Makefile that should catch this kind
of change? It's not just that build target that needs to be remade, it's
everything, yes?
For the reproducer, one actually needs to do
diff --git a/Makefile b/Makefile
index bd33437fdfd..9079131f81e 100644
--- a/Makefile
+++ b/Makefile
@@ -1007,15 +1007,15 @@ KBUILD_CFLAGS += $(call
cc-option,-Wno-format-nonliteral)
KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
ifdef CONFIG_CC_IS_CLANG
-KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
-KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
-KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
+KBUILD_CPPFLAGS += -Qunused-arguments
+KBUILD_CFLAGS += -Wno-format-invalid-specifier
+KBUILD_CFLAGS += -Wno-gnu
# Quiet clang warning: comparison of unsigned expression < 0 is always
false
-KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
+KBUILD_CFLAGS += -Wno-tautological-compare
# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as
the
# source of a reference will be _MergedGlobals and not on of the
whitelisted names.
# See modpost pattern 2
-KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
+KBUILD_CFLAGS += -mno-global-merge
else
# These warnings generated too much noise in a regular build.
Which is what's being done since kernel commit a1494304346a ("kbuild: add
all Clang-specific flags unconditionally"). I actually had this in an
earlier version of this patch series and forgot I removed it.
This seems to apply to envtools and tools-only as well, though make prompts
me for the desired state of symbols that are now reachable, e.g.
ARM64_CRC32. And if I rerun the same command, then it works. It seems like
the config from the previous run is used? I don't know if it's related but
those two commands call make directly ($(Q)$(MAKE) $(build)=<path>). Do you
have something in mind maybe? Or some more commands to run?
I think I partly misunderstood at first. It's not that we switch from
one toolchain to another, it's that we can't (as easily) use gcc for the
target and clang for host tools (and vice-versa) because of how flags
are set now, yes? If so, how does this work in the kernel?
I'm not sure what's happening so it's quite difficult to put into words.
Apply the following to the master branch:
diff --git a/Makefile b/Makefile
index 49d9740327e..9a2367f0a97 100644
--- a/Makefile
+++ b/Makefile
@@ -999,15 +999,15 @@ KBUILD_CFLAGS += $(call
cc-option,-Wno-format-nonliteral)
KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
ifdef CONFIG_CC_IS_CLANG
-KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
-KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
-KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
+KBUILD_CPPFLAGS += -Qunused-arguments
+KBUILD_CFLAGS += -Wno-format-invalid-specifier
+KBUILD_CFLAGS += -Wno-gnu
# Quiet clang warning: comparison of unsigned expression < 0 is always
false
-KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
+KBUILD_CFLAGS += -Wno-tautological-compare
# CLANG uses a _MergedGlobals as optimization, but this breaks
modpost, as the
# source of a reference will be _MergedGlobals and not on of the
whitelisted names.
# See modpost pattern 2
-KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
+KBUILD_CFLAGS += -mno-global-merge
KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
KBUILD_CFLAGS += $(call cc-disable-warning, deprecated-non-prototype)
else
What I do:
make CROSS_COMPILE="aarch64-linux-gnu-" O=build/puma HOSTCC=clang
CC=clang puma-rk3399_defconfig
make CROSS_COMPILE="aarch64-linux-gnu-" O=build/puma HOSTCC=clang
CC=clang V=1
make CROSS_COMPILE="aarch64-linux-gnu-" O=build/puma V=1
That is, I configure the defconfig with clang selected as toolchain,
(successfully) build U-Boot with clang, then rebuild switching to gcc.
What happens is that the last make command prompts me for Kconfig
symbols that are now reachable and thus kconfig doesn't know what to do
with them.
See the (NEW) entries below:
scripts/kconfig/conf --syncconfig Kconfig
*
* Restart config...
*
*
* ARM architecture
*
Enable support for CRC32 instruction (ARM64_CRC32) [Y/n/?] (NEW)
Timer clock frequency (COUNTER_FREQUENCY) [24000000] 24000000
Generate position-independent pre-relocation code (POSITION_INDEPENDENT)
[N/y/?] n
Specify the early stack pointer relative to the .bss section
(INIT_SP_RELATIVE) [N/y/?] n
Emit virtualizable instructions (KVM_VIRT_INS) [N/y/?] n
ARM GICV2 driver (DRIVER_GICV2) [N/y/?] n
ARM GICV3 ITS (GIC_V3_ITS) [N/y/?] n
ARM GICV3 GIC600 SUPPORT (GICV3_SUPPORT_GIC600) [N/y/?] n
Do not enable icache (SYS_ICACHE_OFF) [N/y/?] n
Do not enable icache in SPL (SPL_SYS_ICACHE_OFF) [N/y/?] n
Do not enable dcache (SYS_DCACHE_OFF) [N/y/?] n
Do not enable dcache in SPL (SPL_SYS_DCACHE_OFF) [N/y/?] n
CP15 based cache enabling support (SYS_ARM_CACHE_CP15) [N/y/?] n
MMU-based Paged Memory Management Support (SYS_ARM_MMU) [N/y/?] n
Use the ARM v7 PMSA Compliant MPU (SYS_ARM_MPU) [N/y/?] n
Select the ARM data write cache policy
> 1. Write-back (WB) (SYS_ARM_CACHE_WRITEBACK)
2. Write-through (WT) (SYS_ARM_CACHE_WRITETHROUGH)
3. Write allocation (WA) (SYS_ARM_CACHE_WRITEALLOC)
choice[1-3?]: 1
Enable ARCH_CPU_INIT (ARCH_CPU_INIT) [N/y/?] n
ARM Generic Timer support (SYS_ARCH_TIMER) [Y/n/?] y
Support for ARM SMC Calling Convention (SMCCC) (ARM_SMCCC) [Y/?] y
ARM PL310 L2 cache controller (SYS_L2_PL310) [N/y/?] n
ARM PL310 L2 cache controller in SPL (SPL_SYS_L2_PL310) [N/y/?] n
L2cache off (SYS_L2CACHE_OFF) [N/y/?] n
prepare BOOT0 header (ENABLE_ARM_SOC_BOOT0_HOOK) [Y/?] y
Use an assembly optimized implementation of memcpy (USE_ARCH_MEMCPY)
[N/y/?] (NEW)
Use an assembly optimized implementation of memcpy for SPL
(SPL_USE_ARCH_MEMCPY) [N/y/?] n
Use an assembly optimized implementation of memcpy for TPL
(TPL_USE_ARCH_MEMCPY) [N/y/?] n
Use an assembly optimized implementation of memset (USE_ARCH_MEMSET)
[N/y/?] (NEW)
Use an assembly optimized implementation of memset for SPL
(SPL_USE_ARCH_MEMSET) [N/y/?] n
Use an assembly optimized implementation of memset for TPL
(TPL_USE_ARCH_MEMSET) [N/y/?] n
ARM64 system support AArch32 execution state (ARM64_SUPPORT_AARCH32)
[Y/n/?] y
Target select
1. Airoha SoCs (ARCH_AIROHA)
2. Atmel AT91 (ARCH_AT91)
3. TI DaVinci (ARCH_DAVINCI)
4. Hisilicon HiSTB SoCs (ARCH_HISTB)
5. Marvell Kirkwood (ARCH_KIRKWOOD)
6. Marvell MVEBU family (Armada XP/375/38x/3700/7K/8K) (ARCH_MVEBU)
7. Broadcom BCM283X family (ARCH_BCM283X)
8. Broadcom BCM7XXX family (ARCH_BCMSTB)
9. Broadcom broadband chip family (ARCH_BCMBCA)
10. Support vexpress_ca9x4 (TARGET_VEXPRESS_CA9X4)
11. Support Broadcom Northstar (TARGET_BCMNS)
12. Support Broadcom NS3 (TARGET_BCMNS3)
13. Samsung EXYNOS (ARCH_EXYNOS)
14. Samsung S5PC1XX (ARCH_S5PC1XX)
15. Calxeda Highbank (ARCH_HIGHBANK)
16. ARM Ltd. Integrator family (ARCH_INTEGRATOR)
17. Qualcomm IPQ40xx SoCs (ARCH_IPQ40XX)
18. TI Keystone (ARCH_KEYSTONE)
19. Texas Instruments' K3 Architecture (ARCH_K3)
20. TI OMAP2+ (ARCH_OMAP2PLUS)
21. Amlogic Meson (ARCH_MESON)
22. MediaTek SoCs (ARCH_MEDIATEK)
23. Marvell MMP (ARCH_MMP)
24. NXP LPC32xx platform (ARCH_LPC32XX)
25. NXP i.MX8 platform (ARCH_IMX8)
26. NXP i.MX8M platform (ARCH_IMX8M)
27. NXP i.MX8ULP platform (ARCH_IMX8ULP)
28. NXP i.MX9 platform (ARCH_IMX9)
29. NXP i.MXRT platform (ARCH_IMXRT)
30. NXP i.MX23 family (ARCH_MX23)
31. NXP i.MX28 family (ARCH_MX28)
32. NXP MX7ULP (ARCH_MX7ULP)
33. Freescale MX7 (ARCH_MX7)
34. Freescale MX6 (ARCH_MX6)
35. Freescale MX5 (ARCH_MX5)
36. Nexell S5P4418/S5P6818 SoC (ARCH_NEXELL)
37. Support Nuvoton SoCs (ARCH_NPCM)
38. Apple SoCs (ARCH_APPLE)
39. Actions Semi OWL SoCs (ARCH_OWL)
40. QEMU Virtual Platform (ARCH_QEMU)
41. Renesas ARM SoCs (ARCH_RENESAS)
42. Qualcomm Snapdragon SoCs (ARCH_SNAPDRAGON)
43. Altera SOCFPGA family (ARCH_SOCFPGA)
44. Support sunxi (Allwinner) SoCs (ARCH_SUNXI)
45. ST-Ericsson U8500 Series (ARCH_U8500)
46. Support Xilinx Versal Platform (ARCH_VERSAL)
47. Support AMD Versal Gen 2 Platform (ARCH_VERSAL2)
48. Support Xilinx Versal NET Platform (ARCH_VERSAL_NET)
49. Freescale Vybrid (ARCH_VF610)
50. Xilinx Zynq based platform (ARCH_ZYNQ)
51. Xilinx ZynqMP R5 based platform (ARCH_ZYNQMP_R5)
52. Xilinx ZynqMP based platform (ARCH_ZYNQMP)
53. NVIDIA Tegra (ARCH_TEGRA)
54. Support ARMv8 Arm Ltd. VExpress based boards and models
(ARCH_VEXPRESS64)
55. Support Corstone1000 Platform (TARGET_CORSTONE1000)
56. Support Total Compute Platform (TARGET_TOTAL_COMPUTE)
57. Support ls2080a_emu (TARGET_LS2080A_EMU)
58. Support ls1088aqds (TARGET_LS1088AQDS)
59. Support ls2080aqds (TARGET_LS2080AQDS)
60. Support ls2080ardb (TARGET_LS2080ARDB)
61. Support ls2081ardb (TARGET_LS2081ARDB)
62. Support lx2160ardb (TARGET_LX2160ARDB)
63. Support lx2160aqds (TARGET_LX2160AQDS)
64. Support lx2162aqds (TARGET_LX2162AQDS)
65. Support HiKey 96boards Consumer Edition Platform (TARGET_HIKEY)
66. Support HiKey960 96boards Consumer Edition Platform (TARGET_HIKEY960)
67. Support Poplar 96boards Enterprise Edition Platform (TARGET_POPLAR)
68. Support ls1012aqds (TARGET_LS1012AQDS)
69. Support ls1012ardb (TARGET_LS1012ARDB)
70. Support ls1012a2g5rdb (TARGET_LS1012A2G5RDB)
71. Support ls1012afrwy (TARGET_LS1012AFRWY)
72. Support ls1012afrdm (TARGET_LS1012AFRDM)
73. Support ls1028aqds (TARGET_LS1028AQDS)
74. Support ls1028ardb (TARGET_LS1028ARDB)
75. Support ls1088ardb (TARGET_LS1088ARDB)
76. Support ls1021aqds (TARGET_LS1021AQDS)
77. Support ls1021atwr (TARGET_LS1021ATWR)
78. Support Hitachi-Powergrids SELI8 service unit card
(TARGET_PG_WCOM_SELI8)
79. Support Hitachi-Powergrids EXPU1 service unit card
(TARGET_PG_WCOM_EXPU1)
80. Support ls1021atsn (TARGET_LS1021ATSN)
81. Support ls1021aiot (TARGET_LS1021AIOT)
82. Support ls1043aqds (TARGET_LS1043AQDS)
83. Support ls1043ardb (TARGET_LS1043ARDB)
84. Support ls1046aqds (TARGET_LS1046AQDS)
85. Support ls1046ardb (TARGET_LS1046ARDB)
86. Support ls1046afrwy (TARGET_LS1046AFRWY)
87. Analog Devices SC5XX-processor family (ARCH_SC5XX)
88. Support sl28 (TARGET_SL28)
89. Support ten64 (TARGET_TEN64)
90. Socionext UniPhier SoCs (ARCH_UNIPHIER)
91. Socionext SynQuacer SoCs (ARCH_SYNQUACER)
92. Support STMicroelectronics STM32 MCU with cortex M (ARCH_STM32)
93. Support STMicroelectronics SoCs (ARCH_STI)
94. Support STMicroelectronics STM32MP Socs with cortex A (ARCH_STM32MP)
> 95. Support Rockchip SoCs (ARCH_ROCKCHIP)
96. Support OcteonTX SoCs (ARCH_OCTEONTX)
97. Support OcteonTX2 SoCs (ARCH_OCTEONTX2)
98. Support ThunderX 88xx (TARGET_THUNDERX_88XX)
99. Support Aspeed SoCs (ARCH_ASPEED)
100. Support Phytium Durian Platform (TARGET_DURIAN)
101. Support Phytium Pomelo Platform (TARGET_POMELO)
102. Support Phytium PE2201 Platform (TARGET_PE2201)
103. Support Cortina Presidio ASIC Platform (TARGET_PRESIDIO_ASIC)
104. Xen guest ARM64 (TARGET_XENGUEST_ARM64)
105. Support HPE GXP SoCs (ARCH_GXP)
choice[1-105?]: 95
Support Rockchip PX30 (ROCKCHIP_PX30) [N/y/?] n
Support Rockchip RK3036 (ROCKCHIP_RK3036) [N/y/?] n
Support Rockchip RK3066 (ROCKCHIP_RK3066) [N/y/?] n
Support Rockchip RK3128 (ROCKCHIP_RK3128) [N/y/?] n
Support Rockchip RK3188 (ROCKCHIP_RK3188) [N/y/?] n
Support Rockchip RK3228/RK3229 (ROCKCHIP_RK322X) [N/y/?] n
Support Rockchip RK3288 (ROCKCHIP_RK3288) [N/y/?] n
Support Rockchip RK3308 (ROCKCHIP_RK3308) [N/y/?] n
Support Rockchip RK3328 (ROCKCHIP_RK3328) [N/y/?] n
Support Rockchip RK3368 (ROCKCHIP_RK3368) [N/y/?] n
Support Rockchip RK3399 (ROCKCHIP_RK3399) [Y/n/?] y
Support Rockchip RK3506 (ROCKCHIP_RK3506) [N/y/?] n
Support Rockchip RK3528 (ROCKCHIP_RK3528) [N/y/?] n
Support Rockchip RK3568 (ROCKCHIP_RK3568) [N/y/?] n
Support Rockchip RK3576 (ROCKCHIP_RK3576) [N/y/?] n
Support Rockchip RK3588 (ROCKCHIP_RK3588) [N/y/?] n
Support Rockchip RV1108 (ROCKCHIP_RV1108) [N/y/?] n
Support Rockchip RV1126 (ROCKCHIP_RV1126) [N/y/?] n
Route uart output to usb pins (ROCKCHIP_USB_UART) [N/y/?] n
SPL returns to bootrom (SPL_ROCKCHIP_BACK_TO_BROM) [N/y/?] n
TPL returns to bootrom (TPL_ROCKCHIP_BACK_TO_BROM) [Y/n/?] y
Rockchip common board file (ROCKCHIP_COMMON_BOARD) [Y/n/?] y
Rockchip SPL common board file (SPL_ROCKCHIP_COMMON_BOARD) [Y/n/?] y
Rockchip TPL common board file (TPL_ROCKCHIP_COMMON_BOARD) [Y/n/?] y
Use external TPL binary (ROCKCHIP_EXTERNAL_TPL) [N/y/?] n
Rockchip boot mode flag register address (ROCKCHIP_BOOT_MODE_REG) [0x0] 0x0
Disable device boot on power plug-in
(ROCKCHIP_RK8XX_DISABLE_BOOT_ON_POWERON) [N/y/?] n
Rockchip STIMER support (ROCKCHIP_STIMER) [Y/n/?] y
Size of IRAM reserved in SPL (ROCKCHIP_SPL_RESERVE_IRAM) [0x0] 0x0
SPL requires early-return (for RK3188-style BROM) to BROM
(SPL_ROCKCHIP_EARLYRETURN_TO_BROM) [N/y/?] n
Disable force_jtag feature (ROCKCHIP_DISABLE_FORCE_JTAG) [Y/n/?] y
TPL requires early-return (for RK3188-style BROM) to BROM
(TPL_ROCKCHIP_EARLYRETURN_TO_BROM) [N/y/?] n
Build a SPI image for rockchip (ROCKCHIP_SPI_IMAGE) [Y/n/?] y
Build a maskrom mode image for Rockchip (ROCKCHIP_MASKROM_IMAGE) [N/y/?] n
RK3399 board select
1. Asus Flip C101PA Chromebook (RK3399) (TARGET_CHROMEBOOK_BOB)
2. Samsung Chromebook Plus (RK3399) (TARGET_CHROMEBOOK_KEVIN)
3. RK3399 evaluation board (TARGET_EVB_RK3399)
4. Pinebook Pro (TARGET_PINEBOOK_PRO_RK3399)
5. PinePhone Pro (TARGET_PINEPHONE_PRO_RK3399)
> 6. Theobroma Systems RK3399-Q7 (Puma) (TARGET_PUMA_RK3399)
7. Vamrs Limited Rock960 board family (TARGET_ROCK960_RK3399)
8. Radxa ROCK Pi 4 board (TARGET_ROCKPI4_RK3399)
9. Pine64 Rockpro64 board (TARGET_ROCKPRO64_RK3399)
10. Firefly ROC-RK3399-PC board (TARGET_ROC_PC_RK3399)
choice[1-10?]: 6
Theobroma Systems RK3399-Q7 DDR Option
> 1. DDR3-1333MHz (TARGET_PUMA_RK3399_RAM_DDR3_1333)
2. DDR3-1600MHz (TARGET_PUMA_RK3399_RAM_DDR3_1600)
3. DDR3-1866MHz (TARGET_PUMA_RK3399_RAM_DDR3_1866)
choice[1-3?]: 1
Force cache maintenance to be exclusively by VA (CMO_BY_VA_ONLY) [N/y/?] n
Fix broken ARMv8 generic timer (ARMV8_CNTFRQ_BROKEN) [N/y/?] n
Install crash dump exception vectors (ARMV8_SPL_EXCEPTION_VECTORS) [N/y/?] n
Enable multiple CPUs to enter into U-Boot (ARMV8_MULTIENTRY) [N/y/?] n
Enable data coherency with other cores in cluster (ARMV8_SET_SMPEN)
[Y/n/?] y
Enable switching to running in EL1 (ARMV8_SWITCH_TO_EL1) [N/y/?] n
Use PSCI for reset and shutdown (PSCI_RESET) [Y/n/?] y
Enable PSCI support (ARMV8_PSCI) [N/y/?] n
External aborts and SError interrupt exception are taken in EL3
(ARMV8_EA_EL3_FIRST) [N/y/?] n
Use the event stream for udelay (ARMV8_UDELAY_EVENT_STREAM) [N/y/?] n
*
* General setup
*
Compile also drivers which will not load (COMPILE_TEST) [N/y/?] n
Compile U-Boot with warnings as errors (WERROR) [N/y/?] n
Local version - append to U-Boot release (LOCALVERSION) []
Automatically append version information to the version string
(LOCALVERSION_AUTO) [Y/n/?] y
Optimization level
> 1. Optimize for size (CC_OPTIMIZE_FOR_SIZE)
2. Optimize for speed (CC_OPTIMIZE_FOR_SPEED)
3. Optimize for debugging (CC_OPTIMIZE_FOR_DEBUG)
choice[1-3?]: 1
Allow compiler to uninline functions marked 'inline' in full U-Boot
(OPTIMIZE_INLINING) [N/y/?] n
Allow compiler to uninline functions marked 'inline' in SPL
(SPL_OPTIMIZE_INLINING) [N/y/?] n
Allow compiler to uninline functions marked 'inline' in TPL
(TPL_OPTIMIZE_INLINING) [N/y/?] n
Enable Link Time Optimizations (LTO) [N/y/?] n
Select U-Boot be run as a bootloader for XEN Virtual Machine (XEN) [N/y/?] n
Add arch, board, vendor and soc variables to default environment
(ENV_VARS_UBOOT_CONFIG) [Y/?] y
Number of DRAM banks (NR_DRAM_BANKS) [1] 1
Enable kernel command line setup (SYS_BOOT_GET_CMDLINE) [N/y/?] n
Enable kernel board information setup (SYS_BOOT_GET_KBD) [N/y/?] n
Use a custom location for the initial stack pointer address
(HAS_CUSTOM_SYS_INIT_SP_ADDR) [Y/?] y
Static location for the initial stack pointer
(CUSTOM_SYS_INIT_SP_ADDR) [0x03f00000] 0x03f00000
Enable malloc() pool before relocation (SYS_MALLOC_F) [Y/?] y
Size of malloc() pool before relocation (SYS_MALLOC_F_LEN) [0x10000]
0x10000
Define memory for Dynamic allocation (SYS_MALLOC_LEN) [0x2000000] 0x2000000
Enable malloc() pool in SPL (SPL_SYS_MALLOC_F) [Y/n/?] y
Size of malloc() pool in SPL (SPL_SYS_MALLOC_F_LEN) [0x8000] 0x8000
Enable malloc() pool in TPL (TPL_SYS_MALLOC_F) [Y/n/?] y
Size of malloc() pool in TPL (TPL_SYS_MALLOC_F_LEN) [0x4000] 0x4000
Inform valgrind about memory allocations (VALGRIND) [N/y/?] n
64bit physical address support (PHYS_64BIT) [Y/?] y
64bit fdt address support (FDT_64BIT) [Y/?] y
SPL image used in the combined SPL+U-Boot image (SPL_IMAGE)
[spl/u-boot-spl.bin] spl/u-boot-spl.bin
Recreate an ELF image from raw U-Boot binary (REMAKE_ELF) [N/y/?] n
Build target special images (BUILD_TARGET) []
Define a maximum size for the U-Boot image (HAS_BOARD_SIZE_LIMIT) [N/y/?] n
Use a custom location for the U-Boot linker script (SYS_CUSTOM_LDSCRIPT)
[N/y/?] n
Address in memory to use by default (SYS_LOAD_ADDR) [0x800800] 0x800800
Define max stack size that can be used by U-Boot (STACK_SIZE)
[0x1000000] 0x1000000
Exclude some memory from U-Boot / OS information (SYS_MEM_TOP_HIDE)
[0x0] 0x0
Maximum size in bytes reserved for U-Boot in memory (SYS_MONITOR_LEN) [0] 0
Support for multiprocessor (MP) [N/y/?] n
Text Base (TEXT_BASE) [0x00800000] 0x00800000
Use custom U-Boot Start (HAVE_SYS_UBOOT_START) [N/y/?] n
Determine CPU clock frequency at run-time (DYNAMIC_SYS_CLK_FREQ) [N/y/?] n
CPU clock frequency (SYS_CLK_FREQ) [0] 0
Enable U-Boot API (API) [N/y/?] (NEW)
Then it continues with the build, but using the flags for clang while
using GCC, see:
make -f /home/qschulz/work/upstream/u-boot/scripts/Makefile.autoconf || \
{ rm -f include/config/auto.conf; false; }
mkdir -p include/asm
if [ -d
/home/qschulz/work/upstream/u-boot/arch/arm/mach-rk3399/include/mach ];
then \
dest=arch/arm/mach-rk3399/include/mach; \
else \
dest=arch/arm/include/asm/arch-rk3399; \
fi; \
ln -fsn /home/qschulz/work/upstream/u-boot/$dest include/asm/arch
set -e; mkdir -p include/; trap "rm -f include/.config.h.tmp" EXIT; {
(echo "/* Automatically generated - do not edit */"; echo \#define
CFG_BOARDDIR board/theobroma-systems/puma_rk3399; echo \#include
\<configs/"puma_rk3399".h\> ; echo \#include \<asm/config.h\>; echo
\#include \<linux/kconfig.h\>; echo \#include \<config_fallbacks.h\>;);
} > include/.config.h.tmp; if [ ! -r include/config.h ] || ! cmp -s
include/config.h include/.config.h.tmp; then : ' UPD
include/config.h'; mv -f include/.config.h.tmp include/config.h; fi
aarch64-linux-gnu-gcc -E -Wall -Werror=strict-prototypes
-Wno-trigraphs -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE
-Werror=implicit-function-declaration -Werror=implicit-int
-Wno-format-security -std=gnu11 -ffreestanding -fno-builtin
-fno-delete-null-pointer-checks -Wno-frame-address
-Wno-format-truncation -Wno-format-overflow -Wno-int-in-bool-context
-Wno-address-of-packed-member -Os -fno-stack-protector
-fno-delete-null-pointer-checks -Wno-zero-length-bounds
-Wno-array-bounds -Wno-stringop-overflow -Wno-maybe-uninitialized
-fmacro-prefix-map=/home/qschulz/work/upstream/u-boot/= -gdwarf-4
-fstack-usage -Wno-format-nonliteral -Wno-address-of-packed-member
-Wno-format-invalid-specifier -Wno-gnu -Wno-tautological-compare
-mno-global-merge -Wno-pointer-sign -D__KERNEL__ -D__UBOOT__
-Qunused-arguments -D__ARM__ -ffunction-sections -fdata-sections
-fno-common -ffixed-x18 -pipe -Iinclude
-I/home/qschulz/work/upstream/u-boot/include
-I/home/qschulz/work/upstream/u-boot/arch/arm/include -include
/home/qschulz/work/upstream/u-boot/include/linux/kconfig.h -nostdinc
-isystem /usr/lib/gcc/aarch64-linux-gnu/15/include -DDO_DEPS_ONLY -dM
include/config.h > u-boot.cfg.tmp && { grep 'define CONFIG_'
u-boot.cfg.tmp | sed '/define CONFIG_IS_ENABLED(/d;/define
CONFIG_IF_ENABLED_INT(/d;/define CONFIG_VAL(/d;' > u-boot.cfg; rm
u-boot.cfg.tmp; } || { rm u-boot.cfg.tmp; false; }
aarch64-linux-gnu-gcc: error: unrecognized command-line option
‘-mno-global-merge’; did you mean ‘-Wno-global-module’?
aarch64-linux-gnu-gcc: error: unrecognized command-line option
‘-Qunused-arguments’
make[2]: ***
[/home/qschulz/work/upstream/u-boot/scripts/Makefile.autoconf:84:
u-boot.cfg] Error 1
make[1]: *** No rule to make target 'include/config/auto.conf', needed
by 'include/config/uboot.release'. Stop.
make: *** [Makefile:189: __sub-make] Error 2
If I do nothing but call
make CROSS_COMPILE="aarch64-linux-gnu-" O=build/puma V=1
again, it'll work just fine and compile with GCC flags with the GCC
toolchain (well, I don't get an error anymore, so I'm assumign that
what's happening :) ). So it seems to me that the symbols as used in
Makefile depend on the previous make command generating the .config and
syncconfig is running "too late".
Contrary to what I initially thought, it's not actually related to
U-Boot host tools.
I'm not attempting to mix GCC and clang for host/target building, and I
don't know if this would work in any case. I don't know if this is
something we want to support anyway. As for what the Linux kernel does,
they document[1] LLVM/clang support by telling the user to essentially
use LLVM=1 which they claim is an alias to:
CC=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \
OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump READELF=llvm-readelf \
HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar HOSTLD=ld.lld
They don't really hint at CC and HOSTCC being different as being an
option. Maybe it works, maybe it doesn't?
I did test in the Linux kernel whether they had the same issue but it
doesn't seem like it is the case.
[1] https://www.kernel.org/doc/html/latest/kbuild/llvm.html
Hope this helps,
Cheers,
Quentin
