# git rev-parse -q --verify 3a7e02c040b130b5545e4b115aada7bacd80a2b6^{commit}
# git fetch -q -n -f git://fs.ozlabs.ibm.com/kernel/linus master
# git rev-parse -q --verify 3a7e02c040b130b5545e4b115aada7bacd80a2b6^{commit}
3a7e02c040b130b5545e4b115aada7bacd80a2b6
# git checkout -q -f -B kisskb 3a7e02c040b130b5545e4b115aada7bacd80a2b6
# git clean -qxdf
# < git log -1
# commit 3a7e02c040b130b5545e4b115aada7bacd80a2b6
# Author: Linus Torvalds <torvalds@linux-foundation.org>
# Date:   Fri Jul 26 15:32:27 2024 -0700
# 
#     minmax: avoid overly complicated constant expressions in VM code
#     
#     The minmax infrastructure is overkill for simple constants, and can
#     cause huge expansions because those simple constants are then used by
#     other things.
#     
#     For example, 'pageblock_order' is a core VM constant, but because it was
#     implemented using 'min_t()' and all the type-checking that involves, it
#     actually expanded to something like 2.5kB of preprocessor noise.
#     
#     And when that simple constant was then used inside other expansions:
#     
#       #define pageblock_nr_pages      (1UL << pageblock_order)
#       #define pageblock_start_pfn(pfn)  ALIGN_DOWN((pfn), pageblock_nr_pages)
#     
#     and we then use that inside a 'max()' macro:
#     
#             case ISOLATE_SUCCESS:
#                     update_cached = false;
#                     last_migrated_pfn = max(cc->zone->zone_start_pfn,
#                             pageblock_start_pfn(cc->migrate_pfn - 1));
#     
#     the end result was that one statement expanding to 253kB in size.
#     
#     There are probably other cases of this, but this one case certainly
#     stood out.
#     
#     I've added 'MIN_T()' and 'MAX_T()' macros for this kind of "core simple
#     constant with specific type" use.  These macros skip the type checking,
#     and as such need to be very sparingly used only for obvious cases that
#     have active issues like this.
#     
#     Reported-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
#     Link: https://lore.kernel.org/all/36aa2cad-1db1-4abf-8dd2-fb20484aabc3@lucifer.local/
#     Cc: David Laight <David.Laight@aculab.com>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/korg/gcc-13.1.0-nolibc/sparc64-linux/bin/sparc64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-13.1.0-nolibc/sparc64-linux/bin/sparc64-linux-ld --version
# < git log --format=%s --max-count=1 3a7e02c040b130b5545e4b115aada7bacd80a2b6
# make -s -j 160 ARCH=sparc64 O=/kisskb/build/linus_allmodconfig_sparc64-gcc13 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-13.1.0-nolibc/sparc64-linux/bin/sparc64-linux-  allmodconfig
# < make -s -j 160 ARCH=sparc64 O=/kisskb/build/linus_allmodconfig_sparc64-gcc13 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-13.1.0-nolibc/sparc64-linux/bin/sparc64-linux-  help
# make -s -j 160 ARCH=sparc64 O=/kisskb/build/linus_allmodconfig_sparc64-gcc13 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-13.1.0-nolibc/sparc64-linux/bin/sparc64-linux-  olddefconfig
# make -s -j 160 ARCH=sparc64 O=/kisskb/build/linus_allmodconfig_sparc64-gcc13 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-13.1.0-nolibc/sparc64-linux/bin/sparc64-linux-  
<stdin>:1519:2: warning: #warning syscall clone3 not implemented [-Wcpp]
/kisskb/src/arch/sparc/vdso/vclock_gettime.c:254:1: error: no previous prototype for '__vdso_clock_gettime' [-Werror=missing-prototypes]
  254 | __vdso_clock_gettime(clockid_t clock, struct __kernel_old_timespec *ts)
      | ^~~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/sparc/vdso/vclock_gettime.c:282:1: error: no previous prototype for '__vdso_clock_gettime_stick' [-Werror=missing-prototypes]
  282 | __vdso_clock_gettime_stick(clockid_t clock, struct __kernel_old_timespec *ts)
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/sparc/vdso/vclock_gettime.c:307:1: error: no previous prototype for '__vdso_gettimeofday' [-Werror=missing-prototypes]
  307 | __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
      | ^~~~~~~~~~~~~~~~~~~
/kisskb/src/arch/sparc/vdso/vclock_gettime.c:343:1: error: no previous prototype for '__vdso_gettimeofday_stick' [-Werror=missing-prototypes]
  343 | __vdso_gettimeofday_stick(struct __kernel_old_timeval *tv, struct timezone *tz)
      | ^~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[5]: *** [/kisskb/src/scripts/Makefile.build:244: arch/sparc/vdso/vclock_gettime.o] Error 1
make[4]: *** [/kisskb/src/scripts/Makefile.build:485: arch/sparc/vdso] Error 2
make[4]: *** Waiting for unfinished jobs....
/kisskb/src/kernel/fork.c: In function '__do_sys_clone3':
/kisskb/src/kernel/fork.c:3072:2: error: #warning clone3() entry point is missing, please fix [-Werror=cpp]
 3072 | #warning clone3() entry point is missing, please fix
      |  ^~~~~~~
cc1: all warnings being treated as errors
make[4]: *** [/kisskb/src/scripts/Makefile.build:244: kernel/fork.o] Error 1
make[4]: *** Waiting for unfinished jobs....
make[3]: *** [/kisskb/src/scripts/Makefile.build:485: arch/sparc] Error 2
make[3]: *** Waiting for unfinished jobs....
make[3]: *** [/kisskb/src/scripts/Makefile.build:485: kernel] Error 2
make[2]: *** [/kisskb/src/Makefile:1926: .] Error 2
make[1]: *** [/kisskb/src/Makefile:224: __sub-make] Error 2
make: *** [Makefile:224: __sub-make] Error 2
Command 'make -s -j 160 ARCH=sparc64 O=/kisskb/build/linus_allmodconfig_sparc64-gcc13 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-13.1.0-nolibc/sparc64-linux/bin/sparc64-linux-  ' returned non-zero exit status 2.
# rm -rf /kisskb/build/linus_allmodconfig_sparc64-gcc13
# Build took: 0:12:29.892603