long story short, colleague came to me with a petalinux project wherein the compile of u-boot was failing due to a redefinition of the macro "CONFIG_PANIC_HANG" ... rather than mess with petalinux, i just set up the current master of u-boot (aarch64), used the same configuration and, sure enough:
CC lib/asm-offsets.s In file included from include/config.h:5, from include/common.h:23, from lib/asm-offsets.c:14: include/configs/xilinx_zynqmp.h:97: warning: "CONFIG_PANIC_HANG" redefined #define CONFIG_PANIC_HANG
In file included from ././include/linux/kconfig.h:4, from <command-line>: include/generated/autoconf.h:410: note: this is the location of the previous definition #define CONFIG_PANIC_HANG 1
it would *appear* that this is because xilinx_zynqmp.h defines:
#define CONFIG_PANIC_HANG
but that symbol has been migrated to the Kconfig system, lib/Kconfig:
config PANIC_HANG bool "Do not reset the system on fatal error" help Define this option to stop the system in case of a fatal error, so that you have to reset it manually. This is probably NOT a good idea for an embedded system where you want the system to reboot automatically as fast as possible, but it may be useful during development since you can try to debug the conditions that lead to the situation.
is it safe to assume that this is the problem? i can certainly see how that combination would generate two different macro definitions, and it's just our luck that it seems that is the only header file that does that.
rday