On Sun, Jan 23, 2022 at 4:23 AM Chan Kim <ckim@xxxxxxxxxx> wrote: > > Hello all, > > In linux 5.4.21, when tell the compiler to use no optimzation for function early_fixmap_init as below, > > (I need to compile with O0 to follow what’s happening here using gdb.) > > #pragma GCC push_options > > #pragma GCC optimze ("O0") > > void __init early_fixmap_init(void) > > { > > ... > > } > > #pragma GCC pop_options > > > > I get this compiler error below. (make ARCH=arm64 CROSS_COMPILE=aarch64-none-elf- Image -j24) > > CALL scripts/atomic/check-atomics.sh > > CALL scripts/checksyscalls.sh > > CHK include/generated/compile.h > > CC arch/arm64/mm/mmu.o > > CC drivers/irqchip/irq-gic-v3.o > > In file included from ./include/linux/build_bug.h:5, > > from ./arch/arm64/include/asm/sysreg.h:758, > > from ./arch/arm64/include/asm/cputype.h:126, > > from ./arch/arm64/include/asm/cache.h:8, > > from ./include/linux/cache.h:6, > > from arch/arm64/mm/mmu.c:9: > > ./arch/arm64/include/asm/pgalloc.h: In function '__pgd_populate.constprop': > > ./include/linux/compiler.h:350:38: error: call to '__compiletime_assert_88' declared with attribute error: BUILD_BUG failed > > 350 | _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) > > | ^ > > ./include/linux/compiler.h:331:4: note: in definition of macro '__compiletime_assert' > > 331 | prefix ## suffix(); \ > > | ^~~~~~ > > ./include/linux/compiler.h:350:2: note: in expansion of macro '_compiletime_assert' > > 350 | _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) > > | ^~~~~~~~~~~~~~~~~~~ > > ./include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert' > > 39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) > > | ^~~~~~~~~~~~~~~~~~ > > ./include/linux/build_bug.h:59:21: note: in expansion of macro 'BUILD_BUG_ON_MSG' > > 59 | #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed") > > | ^~~~~~~~~~~~~~~~ > > ./arch/arm64/include/asm/pgalloc.h:88:2: note: in expansion of macro 'BUILD_BUG' > > 88 | BUILD_BUG(); > > | ^~~~~~~~~ > > make[2]: *** [scripts/Makefile.build:265: arch/arm64/mm/mmu.o] Error 1 > > make[1]: *** [scripts/Makefile.build:509: arch/arm64/mm] Error 2 > > make: *** [Makefile:1652: arch/arm64] Error 2 > > make: *** Waiting for unfinished jobs.... > > AR drivers/irqchip/built-in.a > > AR drivers/built-in. > > > > What does this mean and what should I do? > it means that some precondition failed, and you reached a known broken setup. Instead of giving you a broken kernel, its told you that you have to fix this 1st. try making an intermediate output, forex: make init/main.i that should provide hints as to how you got to the BUILD_BUG I dont think banging on -O compile options will help, at least not after seeing GregKH opine on it. > Thanks! > > Chan Kim > > > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies@xxxxxxxxxxxxxxxxx > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies