Re: Personal aarch64 FreeBSD OS build gets SIGSEGV during: ./pmu-events/jevents arm64 /usr/main-src/lib/libpmc/pmu-events/arch libpmc_event [more about cause]

On 9/22/26 08:25, Mark Millard wrote:
> On 9/22/26 08:21, Mark Millard wrote:
>> On 9/22/26 06:43, Alan Somers wrote:
>>> On Sun, Sep 20, 2026 at 10:46 PM Mark Millard <marklmi@yahoo.com> wrote:
>>>>
>>>> On 9/20/26 18:54, Mark Millard wrote:
>>>>> On 9/20/26 11:13, Mark Millard wrote:
>>>>>> [I have CC'd a could of authors with recent libpmc commits. I did not
>>>>>> list any recent libc authors.]
>>>>>>
>>>>>> . . .
>>>>>>
>>>>>
>>>>> I found the type of problem --but it is not a obvious extension of
>>>>> the prior material: META_MODE recorded something that indicates the
>>>>> actual problem . . .
>>>>>
>>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/lib/libpmc/pmu-events/jevents.pieo.meta:R
>>>>> 12651 /usr/include/fts.h
>>>>>
>>>>> The build is using the /usr/include/fts.h from the live old system
>>>>> while trying to build the new system.
>>>>>
>>>>> Given the FTSENT change of layout from old to new, that does not
>>>>> work. Also, this is not something that clearing out /usr/obj/ . . .
>>>>> and rebuilding fixes.
>>>>>
>>>>> The build of lib/libpmc/pmu-events/jevents.* should get the fts.h
>>>>> file from the source tree being built, in my case I was working in
>>>>> /usr/main-src/ so:
>>>>>
>>>>> # find -s /usr/main-src/ -name fts.h -print
>>>>> /usr/main-src/include/fts.h
>>>>>
>>>>> lists a path to the file that should have been used for the build.
>>>>>
>>>>> I expect that this would be a libpmc development issue, not a fts
>>>>> development issue for who solves it.
>>>>>
>>>>>
>>>>> Also: this turns out to not be an arm specific problem.
>>>>>
>>>>>
>>>>
>>>> The problematic include handling for building system updates extends far
>>>> beyond the specific example in jevents.pieo.meta : All but 8 of the many
>>>> include file usages were strictly tied to the old live system instead of
>>>> to the new system's source tree (to some degree):
>>>> (The ones that mention main-src are those that involve the source tree
>>>> that I was doing the build for.)
>>>>
>>>> # grep -e /include/ -e '\.h$'
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/lib/libpmc/pmu-events/jevents.pieo.meta
>>>> R 12651 /usr/include/sys/param.h
>>>> R 12651 /usr/include/sys/_null.h
>>>> R 12651 /usr/include/sys/_param.h
>>>> R 12651 /usr/include/sys/types.h
>>>> R 12651
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/tmp/legacy/usr/include/sys/cdefs.h
>>>> R 12651
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/tmp/legacy/usr/include/sys/_decls.h
>>>> R 12651
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/tmp/legacy/usr/include/sys/_visible.h
>>>> R 12651 /usr/include/machine/endian.h
>>>> R 12651 /usr/include/sys/_types.h
>>>> R 12651 /usr/include/machine/_types.h
>>>> R 12651 /usr/include/sys/_endian.h
>>>> R 12651 /usr/include/sys/_offsetof.h
>>>> R 12651 /usr/include/sys/_pthreadtypes.h
>>>> R 12651 /usr/include/sys/_stdint.h
>>>> R 12651 /usr/include/sys/bitcount.h
>>>> R 12651 /usr/include/sys/select.h
>>>> R 12651 /usr/include/sys/_sigset.h
>>>> R 12651 /usr/include/sys/_timeval.h
>>>> R 12651 /usr/include/sys/timespec.h
>>>> R 12651 /usr/include/sys/_timespec.h
>>>> R 12651 /usr/include/sys/syslimits.h
>>>> R 12651 /usr/include/sys/signal.h
>>>> R 12651 /usr/include/sys/_sigaltstack.h
>>>> R 12651 /usr/include/sys/_sigval.h
>>>> R 12651 /usr/include/machine/_limits.h
>>>> R 12651 /usr/include/machine/signal.h
>>>> R 12651 /usr/include/machine/param.h
>>>> R 12651 /usr/include/sys/_align.h
>>>> R 12651 /usr/include/sys/limits.h
>>>> R 12651 /usr/include/sys/_maxphys.h
>>>> R 12651 /usr/include/sys/resource.h
>>>> R 12651 /usr/include/sys/stat.h
>>>> R 12651 /usr/include/sys/time.h
>>>> R 12651 /usr/include/sys/_clock_id.h
>>>> R 12651 /usr/include/time.h
>>>> R 12651 /usr/include/xlocale/_time.h
>>>> R 12651 /usr/include/ctype.h
>>>> R 12651 /usr/include/_ctype.h
>>>> R 12651 /usr/include/runetype.h
>>>> R 12651 /usr/include/xlocale/_ctype.h
>>>> R 12651 /usr/include/dirent.h
>>>> R 12651 /usr/include/sys/dirent.h
>>>> R 12651 /usr/include/errno.h
>>>> R 12651 /usr/include/libgen.h
>>>> R 12651 /usr/include/limits.h
>>>> R 12651 /usr/include/stdarg.h
>>>> R 12651 /usr/include/sys/_stdarg.h
>>>> R 12651
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/tmp/legacy/usr/include/stddef.h
>>>> R 12651 /usr/include/stddef.h
>>>> R 12651 /usr/include/stdio.h
>>>> R 12651 /usr/include/stdlib.h
>>>> R 12651 /usr/include/string.h
>>>> R 12651 /usr/include/strings.h
>>>> R 12651 /usr/include/xlocale/_strings.h
>>>> R 12651 /usr/include/xlocale/_string.h
>>>> R 12651 /usr/include/unistd.h
>>>> R 12651 /usr/include/sys/unistd.h
>>>> R 12651 /usr/include/ftw.h
>>>> R 12651 /usr/main-src/lib/libpmc/pmu-events/list.h
>>>> R 12651 /usr/main-src/lib/libpmc/pmu-events/jsmn.h
>>>> R 12651 /usr/main-src/lib/libpmc/pmu-events/json.h
>>>> R 12651 /usr/include/stdbool.h
>>>> R 12651 /usr/main-src/lib/libpmc/pmu-events/pmu-events.h
>>>> R 12651 /usr/include/fts.h
>>>>
>>>>
>>>> Some of those may be lower risk of incompatible changes than others but
>>>> the general trend is not good for doing system builds when layout
>>>> changes or other incompatibilities are introduced.
>>>>
>>>> Of course, there are some things that are built for operation on the
>>>> older system instead of the newer one. So the classification is case by
>>>> case across the various *.meta files.
>>>>
>>>>
>>>> Taking a quick stab at finding other examples (incomplete because of the
>>>> failed build):
>>>>
>>>> # find -s /usr/obj/BUILDs/main-CA76-nodbg-clang/ -name \*.meta -exec
>>>> grep -l -e ' /usr/include/' {} \; | grep -v /tmp/obj-tools/
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/bin/csh/gethost.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/bin/sh/mknodes.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/bin/sh/mksyntax.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/host-osreldate.h.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/lib/libmagic/mkmagic.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/lib/libpmc/pmu-events/jevents.pieo.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/lib/libpmc/pmu-events/jsmn.pieo.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/lib/libpmc/pmu-events/json.pieo.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/lib/ncurses/tinfo/make_hash.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/lib/ncurses/tinfo/make_keys.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/rescue/rescue/usr/main-src/bin/csh/gethost.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/rescue/rescue/usr/main-src/bin/sh/mknodes.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/rescue/rescue/usr/main-src/bin/sh/mksyntax.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/share/syscons/scrnmaps/armscii8-2haik8.mk.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/share/syscons/scrnmaps/iso-8859-1_to_cp437.mk.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/share/syscons/scrnmaps/iso-8859-4_for_vga9.mk.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/share/syscons/scrnmaps/iso-8859-7_to_cp437.mk.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/share/syscons/scrnmaps/koi8-r2cp866.mk.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/share/syscons/scrnmaps/koi8-u2cp866u.mk.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/share/syscons/scrnmaps/us-ascii_to_cp437.mk.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/usr.bin/awk/maketab.meta
>>>> /usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/usr.bin/vi/catalog/dump.meta
>>>>
>>>>
>>>> --
>>>> ===
>>>> Mark Millard
>>>> marklmi at yahoo.com
>>>
>>> Interesting find.  And I can reproduce it, partially.  If I build
>>> 16.0-CURRENT from a 15.1 host, and look at the generated symbols:
>>>
>>>> objdump -T /usr/obj/.../amd64.amd64/lib/libpmc/pmu-events/jevents.full | grep fts_
>>> 0000000000000000      DF *UND*  0000000000000000 (FBSD_1.5)   fts_open
>>> 0000000000000000      DF *UND*  0000000000000000 (FBSD_1.5)   fts_read
>>> 0000000000000000      DF *UND*  0000000000000000 (FBSD_1.5)   fts_close
>>>
>>> I see the FBSD_1.5 version of those symbols.  It should be FBSD_1.9
>>> instead.  Indeed, if I build from a 16.0 host I do see the FBSD_1.9
>>> symbols.  So the build is definitely wrong.  But that doesn't quite
>>> explain why you would get a segfault.  Linking to the FBSD_1.5 symbols
>>> while using the old header files should work fine.  So I wonder if the
>>> build is somehow including a mixture of old header files and new ones.
>>> That would explain a segfault.
>>>
>>>
>>
>> Yes, it is getting a mnixture: one place gets /usr/inbclude/fts.h .
>>
>> Using find for .meta files in the build directorty tree and grep for
>> fts.h in such files I find:
>>
>> ) The odd:
>>
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libpmc/pmu-events/jevents.pieo.meta:R
>> 77658 /usr/include/fts.h
>>
>> ) Mostly reference to: /usr/main-src/include/fts.h
>>   (I'll not show the list of places.)
>>
>> For reference:
>>
>> # diff -u /usr/include/fts.h /usr/main-src/include/fts.h
>> --- /usr/include/fts.h	2025-05-11 07:29:42.791259000 -0700
>> +++ /usr/main-src/include/fts.h	2026-09-18 16:13:35.766402000 -0700
>> @@ -1,4 +1,4 @@
>> -/*-
>> +/*
>>   * SPDX-License-Identifier: BSD-3-Clause
>>   *
>>   * Copyright (c) 1989, 1993
>> @@ -92,6 +92,8 @@
>>  	char *fts_path;			/* root path */
>>  	int fts_errno;			/* errno for this node */
>>  	int fts_symfd;			/* fd for symlink */
>> +	int fts_dirfd;                  /* fd for this directory, if a
>> directory */
>> +	int __fts_reserved[3];          /* reserved for future use */
>>  	__size_t fts_pathlen;		/* strlen(fts_path) */
>>  	__size_t fts_namelen;		/* strlen(fts_name) */
>>
>> @@ -146,6 +148,8 @@
>>  #define	 fts_get_stream(ftsent)	((ftsent)->fts_fts)
>>  FTS	*fts_open(char * const *, int,
>>  	    int (*)(const FTSENT * const *, const FTSENT * const *));
>> +FTS	*fts_openat(int, char * const *, int,
>> +	    int (*)(const FTSENT * const *, const FTSENT * const *));
>>  #ifdef __BLOCKS__
>>  FTS	*fts_open_b(char * const *, int,
>>  	    int (^)(const FTSENT * const *, const FTSENT * const *));
>>
>> ) A rereference:
>>
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libsysdecode/ioctl.c.tmp.meta:R
>> 64787 ./fts.h
>>
>> There are a lot of ./. . ./*.h paths in this meta file. If I gatehr
>> right, these are relative to:
>>
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/
>>
>> For reference:
>>
>> # diff -u
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/main-src/include/fts.h
>> #
>>
>>
>> ) There are references:
>>
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libclang_rt/asan/sanitizer_common_sanitizer_platform_limits_freebsd.o.meta:R
>> 60898
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libclang_rt/asan_dynamic/sanitizer_common_sanitizer_platform_limits_freebsd.pico.meta:R
>> 61150
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libclang_rt/cfi/sanitizer_common_sanitizer_platform_limits_freebsd.o.meta:R
>> 60129
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libclang_rt/cfi_diag/sanitizer_common_sanitizer_platform_limits_freebsd.o.meta:R
>> 60241
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libclang_rt/msan/sanitizer_common_sanitizer_platform_limits_freebsd.o.meta:R
>> 61596
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libclang_rt/stats/sanitizer_common_sanitizer_platform_limits_freebsd.o.meta:R
>> 61726
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libclang_rt/tsan/sanitizer_common_sanitizer_platform_limits_freebsd.o.meta:R
>> 61835
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libclang_rt/ubsan_standalone/sanitizer_common_sanitizer_platform_limits_freebsd.o.meta:R
>> 62121
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libclang_rt/xray/sanitizer_common_sanitizer_platform_limits_freebsd.o.meta:R
>> 62367
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>>
>> For reference:
>>
>> # diff -u
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/tmp/usr/include/fts.h
>> /usr/main-src/include/fts.h
>> #
>>
>> ) I ignore here references in . . ./include/_INCSINS.meta
>>
>>
>> So, just the one example:
> 
> Sorry, poor wording above. Missing: of fts.h
> 
>>
>> /usr/obj/BUILDs/main-CA76-dbg-clang/usr/main-src/arm64.aarch64/lib/libpmc/pmu-events/jevents.pieo.meta:R
>> 77658 /usr/include/fts.h
>>
>>
> 
> jevents.pieo.meta shows lots of other *.h files incorrectly from the
> /usr/include/ area as well.
> 

My hypothesis is that the:

-I/usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/tmp/legacy/usr/include

in the below CMD line from the .meta file is ineffective because what it
references has not been populated yet and so /usr/include/ is being used
by default.

# Meta data file
/usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/lib/libpmc/pmu-events/jevents.pieo.meta
CMD cc -fpie -DPIC   -O2 -pipe -fno-common -Wno-cast-qual
-mcpu=cortex-a76 -fPIE -DNDEBUG  -g -gz=zlib -std=gnu17
-Wno-format-zero-length  -Wsystem-headers -Wall -Wno-format-y2k -W
-Wno-unused-paramet
er -Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith
-Wno-uninitialized -Wno-pointer-sign -Wdate-time -Wno-empty-body
-Wno-string-plus-int -Wno-unused-const-variable -Wno-error=unused-but-set-p
arameter -Wno-error=cast-function-type-mismatch
-Wno-tautological-compare -Wno-unused-value -Wno-parentheses-equality
-Wno-unused-function -Wno-enum-conversion -Wno-unused-local-typedef
-Wno-address-o
f-packed-member  -Qunused-arguments
-I/usr/obj/BUILDs/main-CA76-nodbg-clang/usr/main-src/arm64.aarch64/tmp/legacy/usr/include
 -c /usr/main-src/lib/libpmc/pmu-events/jevents.c -o jevents.pieo
. . .

Also note that there is only the one -I . The
lib/libpmc/pmu-events/Makefile has only:

PROG=	jevents
SRCS=	jevents.c jsmn.c json.c
CFLAGS+= -Wno-cast-qual
MAN=

build-tools: jevents

.include <bsd.prog.mk>


The Makefile.depends has only:

# Autogenerated - do NOT edit!

DIRDEPS = \


.include <dirdeps.mk>

.if ${DEP_RELDIR} == ${_DEP_RELDIR}
# local dependencies - needed for -jN in clean tree
.endif


Nothing is supplying an appropriate -I usage for the context --or
something is out of sequence so that the include files needed are not
yet in place.


-- 
===
Mark Millard
marklmi at yahoo.com