[Bug libgcc/103004] New: [12 regression] breaks lots on powerpc BE

[Bug libgcc/103004] New: [12 regression] breaks lots on powerpc BE

[seurer at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103004

            Bug ID: 103004
           Summary: [12 regression] breaks lots on powerpc BE
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libgcc
          Assignee: unassigned at gcc dot gnu.org
          Reporter: seurer at gcc dot gnu.org
  Target Milestone: ---

commit b7561b5d2443f1d5f54f5177f0fb1a13c4205856
Author: Raphael Moreira Zinsly <rzinsly@linux.ibm.com>
Date:   Tue Oct 5 15:32:52 2021 -0300

    libgcc: Add a backchain fallback to _Unwind_Backtrace() on PowerPC


It looks like this change broke most if not all the asan tests on powerpc64 BE,
a bunch of the go tests, and several more.

These are from a run on a powerpc64 BE power 8 machine:

previous run: g:b47490c572c5938f887b54240af6096a7c90f640, r12-4415
this run    : g:b7561b5d2443f1d5f54f5177f0fb1a13c4205856, r12-4416

New failures:

FAIL: archive/tar
FAIL: archive/zip
FAIL: bufio
FAIL: bytes
FAIL: c-c++-common/asan/alloca_big_alignment.c   -O0  output pattern test
FAIL: c-c++-common/asan/alloca_big_alignment.c   -O1  output pattern test
FAIL: c-c++-common/asan/alloca_big_alignment.c   -O2  output pattern test
FAIL: c-c++-common/asan/alloca_big_alignment.c   -O2 -flto
-fno-use-linker-plugin -flto-partition=none  output pattern test
FAIL: c-c++-common/asan/alloca_big_alignment.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/alloca_big_alignment.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/alloca_big_alignment.c   -Os  output pattern test
FAIL: c-c++-common/asan/alloca_detect_custom_size.c   -O0  output pattern test
FAIL: c-c++-common/asan/alloca_detect_custom_size.c   -O1  output pattern test
FAIL: c-c++-common/asan/alloca_detect_custom_size.c   -O2  output pattern test
FAIL: c-c++-common/asan/alloca_detect_custom_size.c   -O2 -flto
-fno-use-linker-plugin -flto-partition=none  output pattern test
FAIL: c-c++-common/asan/alloca_detect_custom_size.c   -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/alloca_detect_custom_size.c   -O3 -g  output pattern
test
FAIL: c-c++-common/asan/alloca_detect_custom_size.c   -Os  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_partial.c   -O0  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_partial.c   -O1  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_partial.c   -O2  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_partial.c   -O2 -flto
-fno-use-linker-plugin -flto-partition=none  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_partial.c   -O2 -flto
-fuse-linker-plugin -fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_partial.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_partial.c   -Os  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_right.c   -O0  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_right.c   -O1  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_right.c   -O2  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_right.c   -O2 -flto
-fno-use-linker-plugin -flto-partition=none  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_right.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_right.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/alloca_overflow_right.c   -Os  output pattern test
FAIL: c-c++-common/asan/alloca_underflow_left.c   -O0  output pattern test
FAIL: c-c++-common/asan/alloca_underflow_left.c   -O1  output pattern test
FAIL: c-c++-common/asan/alloca_underflow_left.c   -O2  output pattern test
FAIL: c-c++-common/asan/alloca_underflow_left.c   -O2 -flto
-fno-use-linker-plugin -flto-partition=none  output pattern test
FAIL: c-c++-common/asan/alloca_underflow_left.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/alloca_underflow_left.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/alloca_underflow_left.c   -Os  output pattern test
FAIL: c-c++-common/asan/global-overflow-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/global-overflow-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/global-overflow-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/global-overflow-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  output pattern test
FAIL: c-c++-common/asan/global-overflow-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/global-overflow-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/global-overflow-1.c   -Os  output pattern test
FAIL: c-c++-common/asan/halt_on_error-1.c   -O0  execution test
FAIL: c-c++-common/asan/halt_on_error-1.c   -O1  execution test
FAIL: c-c++-common/asan/halt_on_error-1.c   -O2  execution test
FAIL: c-c++-common/asan/halt_on_error-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  execution test
FAIL: c-c++-common/asan/halt_on_error-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  execution test
FAIL: c-c++-common/asan/halt_on_error-1.c   -O3 -g  execution test
FAIL: c-c++-common/asan/halt_on_error-1.c   -Os  execution test
FAIL: c-c++-common/asan/heap-overflow-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/heap-overflow-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/heap-overflow-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/heap-overflow-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  output pattern test
FAIL: c-c++-common/asan/heap-overflow-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/heap-overflow-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/heap-overflow-1.c   -Os  output pattern test
FAIL: c-c++-common/asan/memcmp-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/memcmp-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/memcmp-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/memcmp-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  output pattern test
FAIL: c-c++-common/asan/memcmp-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/memcmp-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/memcmp-1.c   -Os  output pattern test
FAIL: c-c++-common/asan/null-deref-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/null-deref-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/null-deref-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/null-deref-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  output pattern test
FAIL: c-c++-common/asan/null-deref-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/null-deref-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/null-deref-1.c   -Os  output pattern test
FAIL: c-c++-common/asan/pointer-compare-1.c   -O0  execution test
FAIL: c-c++-common/asan/pointer-compare-1.c   -O1  execution test
FAIL: c-c++-common/asan/pointer-compare-1.c   -O2  execution test
FAIL: c-c++-common/asan/pointer-compare-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  execution test
FAIL: c-c++-common/asan/pointer-compare-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  execution test
FAIL: c-c++-common/asan/pointer-compare-1.c   -O3 -g  execution test
FAIL: c-c++-common/asan/pointer-compare-1.c   -Os  execution test
FAIL: c-c++-common/asan/pointer-subtract-1.c   -O0  execution test
FAIL: c-c++-common/asan/pointer-subtract-1.c   -O1  execution test
FAIL: c-c++-common/asan/pointer-subtract-1.c   -O2  execution test
FAIL: c-c++-common/asan/pointer-subtract-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  execution test
FAIL: c-c++-common/asan/pointer-subtract-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  execution test
FAIL: c-c++-common/asan/pointer-subtract-1.c   -O3 -g  execution test
FAIL: c-c++-common/asan/pointer-subtract-1.c   -Os  execution test
FAIL: c-c++-common/asan/pr64820.c   -O0  output pattern test
FAIL: c-c++-common/asan/pr64820.c   -O1  output pattern test
FAIL: c-c++-common/asan/pr64820.c   -O2  output pattern test
FAIL: c-c++-common/asan/pr64820.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  output pattern test
FAIL: c-c++-common/asan/pr64820.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/pr64820.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/pr64820.c   -Os  output pattern test
FAIL: c-c++-common/asan/pr70541.c   -O0  output pattern test
FAIL: c-c++-common/asan/sanity-check-pure-c-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/sanity-check-pure-c-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/sanity-check-pure-c-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/sanity-check-pure-c-1.c   -O2 -flto
-fno-use-linker-plugin -flto-partition=none  output pattern test
FAIL: c-c++-common/asan/sanity-check-pure-c-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/sanity-check-pure-c-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/sanity-check-pure-c-1.c   -Os  output pattern test
FAIL: c-c++-common/asan/stack-overflow-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/stack-overflow-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/stack-overflow-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/stack-overflow-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  output pattern test
FAIL: c-c++-common/asan/stack-overflow-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/stack-overflow-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/stack-overflow-1.c   -Os  output pattern test
FAIL: c-c++-common/asan/strip-path-prefix-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/strip-path-prefix-1.c   -O2 -flto
-fno-use-linker-plugin -flto-partition=none  output pattern test
FAIL: c-c++-common/asan/strip-path-prefix-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/strlen-overflow-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/strlen-overflow-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/strlen-overflow-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/strlen-overflow-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/strlen-overflow-1.c   -Os  output pattern test
FAIL: c-c++-common/asan/strncpy-overflow-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/strncpy-overflow-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/strncpy-overflow-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/strncpy-overflow-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  output pattern test
FAIL: c-c++-common/asan/strncpy-overflow-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/strncpy-overflow-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/strncpy-overflow-1.c   -Os  output pattern test
FAIL: c-c++-common/asan/use-after-free-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/use-after-free-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/use-after-free-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/use-after-free-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  output pattern test
FAIL: c-c++-common/asan/use-after-free-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/use-after-free-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/use-after-free-1.c   -Os  output pattern test
FAIL: c-c++-common/asan/use-after-return-1.c   -O0  output pattern test
FAIL: c-c++-common/asan/use-after-return-1.c   -O1  output pattern test
FAIL: c-c++-common/asan/use-after-return-1.c   -O2  output pattern test
FAIL: c-c++-common/asan/use-after-return-1.c   -O2 -flto -fno-use-linker-plugin
-flto-partition=none  output pattern test
FAIL: c-c++-common/asan/use-after-return-1.c   -O2 -flto -fuse-linker-plugin
-fno-fat-lto-objects  output pattern test
FAIL: c-c++-common/asan/use-after-return-1.c   -O3 -g  output pattern test
FAIL: c-c++-common/asan/use-after-return-1.c   -Os  output pattern test
FAIL: cmd/go/internal/cache
FAIL: cmd/go/internal/fsys
FAIL: cmd/go/internal/generate
FAIL: cmd/go/internal/get
FAIL: cmd/go/internal/imports
FAIL: cmd/go/internal/lockedfile
FAIL: cmd/go/internal/lockedfile/internal/filelock
FAIL: cmd/go/internal/modconv
FAIL: cmd/go/internal/modfetch
FAIL: cmd/go/internal/modfetch/codehost
FAIL: cmd/go/internal/modload
FAIL: cmd/go/internal/mvs
FAIL: cmd/go/internal/par
FAIL: cmd/go/internal/search
FAIL: cmd/go/internal/str
FAIL: cmd/go/internal/test
FAIL: cmd/go/internal/txtar
FAIL: cmd/go/internal/vcs
FAIL: cmd/go/internal/work
FAIL: cmd/internal/buildid
FAIL: cmd/internal/edit
FAIL: cmd/internal/objabi
FAIL: cmd/internal/pkgpath
FAIL: cmd/internal/test2json
FAIL: compress/bzip2
FAIL: compress/flate
FAIL: compress/gzip
FAIL: compress/lzw
FAIL: compress/zlib
FAIL: container/heap
FAIL: container/list
FAIL: container/ring
FAIL: context
FAIL: crypto
FAIL: crypto/aes
FAIL: crypto/cipher
FAIL: crypto/des
FAIL: crypto/dsa
FAIL: crypto/ecdsa
FAIL: crypto/ed25519
FAIL: crypto/ed25519/internal/edwards25519
FAIL: crypto/ed25519/internal/edwards25519/field
FAIL: crypto/elliptic
FAIL: crypto/elliptic/internal/fiat
FAIL: crypto/hmac
FAIL: crypto/internal/subtle
FAIL: crypto/md5
FAIL: crypto/rand
FAIL: crypto/rc4
FAIL: crypto/rsa
FAIL: crypto/sha1
FAIL: crypto/sha256
FAIL: crypto/sha512
FAIL: crypto/subtle
FAIL: crypto/tls
FAIL: crypto/x509
FAIL: database/sql
FAIL: database/sql/driver
FAIL: debug/dwarf
FAIL: debug/elf
FAIL: debug/macho
FAIL: debug/pe
FAIL: debug/plan9obj
FAIL: encoding/ascii85
FAIL: encoding/asn1
FAIL: encoding/base32
FAIL: encoding/base64
FAIL: encoding/binary
FAIL: encoding/csv
FAIL: encoding/gob
FAIL: encoding/hex
FAIL: encoding/pem
FAIL: encoding/xml
FAIL: errors
FAIL: expvar
FAIL: flag
FAIL: fmt

FAIL: g++.dg/abi/forced.C  -std=gnu++14 execution test
FAIL: g++.dg/abi/forced.C  -std=gnu++17 execution test
FAIL: g++.dg/abi/forced.C  -std=gnu++2a execution test
FAIL: g++.dg/abi/forced.C  -std=gnu++98 execution test

FAIL: g++.dg/asan/asan_test.C   -O2 
AddressSanitizer_AtoiAndFriendsOOBTestAtoi(array + 11) output pattern test
...hundreds more...
FAIL: g++.dg/asan/use-after-scope-types-5.C   -Os  output pattern test

FAIL: g++.dg/eh/forced1.C  -std=c++14 execution test
FAIL: g++.dg/eh/forced1.C  -std=c++17 execution test
FAIL: g++.dg/eh/forced1.C  -std=c++2a execution test
FAIL: g++.dg/eh/forced1.C  -std=c++98 execution test
FAIL: gfortran.dg/backtrace_1.f90   -O0  execution test
FAIL: gfortran.dg/backtrace_1.f90   -O1  execution test
FAIL: gfortran.dg/backtrace_1.f90   -O2  execution test
FAIL: gfortran.dg/backtrace_1.f90   -O3 -fomit-frame-pointer -funroll-loops
-fpeel-loops -ftracer -finline-functions  execution test
FAIL: gfortran.dg/backtrace_1.f90   -Os  execution test

FAIL: go.go-torture/execute/array-1.go execution,  -O0 
...hundreds more...
FAIL: go.test/test/zerodivide.go execution,  -O2 -g 
FAIL: go/ast
FAIL: go/build
FAIL: go/build/constraint
FAIL: go/constant
FAIL: go/doc
FAIL: go/format
FAIL: go/importer
FAIL: go/internal/gccgoimporter
FAIL: go/internal/gcimporter
FAIL: go/internal/srcimporter
FAIL: go/parser
FAIL: go/printer
FAIL: go/scanner
FAIL: go/token
FAIL: go/types
FAIL: hash
FAIL: hash/adler32
FAIL: hash/crc32
FAIL: hash/crc64
FAIL: hash/fnv
FAIL: hash/maphash
FAIL: html
FAIL: html/template
FAIL: image
FAIL: image/color
FAIL: image/draw
FAIL: image/jpeg
FAIL: image/png
FAIL: index/suffixarray
FAIL: internal/cpu
FAIL: internal/execabs
FAIL: internal/fmtsort
FAIL: internal/itoa
FAIL: internal/poll
FAIL: internal/profile
FAIL: internal/reflectlite
FAIL: internal/singleflight
FAIL: internal/trace
FAIL: internal/unsafeheader
FAIL: internal/xcoff
FAIL: io
FAIL: io/fs
FAIL: io/ioutil
FAIL: log
FAIL: log/syslog
FAIL: math
FAIL: math/bits
FAIL: math/cmplx
FAIL: math/rand
FAIL: mime
FAIL: mime/multipart
FAIL: mime/quotedprintable
FAIL: net
FAIL: net/http
FAIL: net/http/cgi
FAIL: net/http/cookiejar
FAIL: net/http/fcgi
FAIL: net/http/httptest
FAIL: net/http/httptrace
FAIL: net/http/httputil
FAIL: net/http/internal
FAIL: net/http/internal/ascii
FAIL: net/http/pprof
FAIL: net/internal/socktest
FAIL: net/mail
FAIL: net/rpc
FAIL: net/rpc/jsonrpc
FAIL: net/smtp
FAIL: net/textproto
FAIL: net/url
FAIL: os
FAIL: os/exec
FAIL: os/signal
FAIL: os/user
FAIL: path
FAIL: path/filepath
FAIL: reflect
FAIL: regexp
FAIL: regexp/syntax
FAIL: runtime
FAIL: runtime/cgo
FAIL: runtime/internal/atomic
FAIL: runtime/internal/math
FAIL: runtime/internal/sys
FAIL: runtime/metrics
FAIL: runtime/pprof
FAIL: runtime/trace
FAIL: sort
FAIL: strconv
FAIL: strings
FAIL: sync
FAIL: sync/atomic
FAIL: syscall
FAIL: testing
FAIL: testing/fstest
FAIL: testing/iotest
FAIL: testing/quick
FAIL: text/scanner
FAIL: text/tabwriter
FAIL: text/template
FAIL: text/template/parse
FAIL: time
FAIL: unicode
FAIL: unicode/utf16
FAIL: unicode/utf8

[Bug libgcc/103004] [12 regression] breaks lots on powerpc BE

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103004

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |build
   Target Milestone|---                         |12.0

[Bug libgcc/103004] [12 regression] r12-4416 breaks backtrace on PPC64 Big-endian

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103004

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1

[Bug libgcc/103004] [12 regression] r12-4416 breaks backtrace on PPC64 Big-endian

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103004

David Edelsohn <dje at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dje at gcc dot gnu.org
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2021-11-03
             Status|UNCONFIRMED                 |NEW

--- Comment #1 from David Edelsohn <dje at gcc dot gnu.org> ---
Confirmed.

[Bug libgcc/103004] [12 regression] r12-4416 breaks backtrace on PPC64 Big-endian

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103004

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I see this on powerpc64le-unknown-linux-gnu:

./md-unwind-support.h:398:6: warning: no previous prototype for
‘ppc_backchain_fallback’ [-Wmissing-prototypes]

[Bug libgcc/103004] [12 regression] r12-4416 breaks backtrace on PPC64 Big-endian

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103004

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I think the warning should be fixed with following, just need to test it:

--- libgcc/config/rs6000/linux-unwind.h.jj      2021-10-15 11:59:16.227682621
+0200
+++ libgcc/config/rs6000/linux-unwind.h 2021-11-09 11:42:06.840353422 +0100
@@ -395,7 +395,8 @@ struct frame_layout
 };


-void ppc_backchain_fallback (struct _Unwind_Context *context, void *a)
+static void
+ppc_backchain_fallback (struct _Unwind_Context *context, void *a)
 {
   struct frame_layout *current;
   struct trace_arg *arg = a;

[Bug libgcc/103004] [12 regression] r12-4416 breaks backtrace on PPC64 Big-endian

[rzinsly at linux dot ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103004

--- Comment #4 from Raphael M Zinsly <rzinsly at linux dot ibm.com> ---
On a system with an old toolchain I'm seeing (In reply to Jakub Jelinek from
comment #3)
> I think the warning should be fixed with following, just need to test it:
> 
> --- libgcc/config/rs6000/linux-unwind.h.jj	2021-10-15 11:59:16.227682621
> +0200
> +++ libgcc/config/rs6000/linux-unwind.h	2021-11-09 11:42:06.840353422 +0100
> @@ -395,7 +395,8 @@ struct frame_layout
>  };
>  
>  
> -void ppc_backchain_fallback (struct _Unwind_Context *context, void *a)
> +static void
> +ppc_backchain_fallback (struct _Unwind_Context *context, void *a)
>  {
>    struct frame_layout *current;
>    struct trace_arg *arg = a;

That works, I included in the proposed patch
(https://gcc.gnu.org/pipermail/gcc-patches/2021-November/584043.html), thanks!

[Bug libgcc/103004] [12 regression] r12-4416 breaks backtrace on PPC64 Big-endian

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103004

--- Comment #5 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Bah, I typoed the PR id:

commit 8d71d3a317236ab4a69f441cf867a43aeb448150
Author: Raphael Moreira Zinsly <rzinsly@linux.ibm.com>
Date:   Thu Nov 11 11:40:10 2021 -0300

    libgcc: Fix backtrace fallback on PowerPC Big-endian

    At the end of the backtrace stream _Unwind_Find_FDE() may not be able
    to find the frame unwind info and will later call the backtrace fallback
    instead of finishing. This occurs when using an old libc on ppc64 due to
    dl_iterate_phdr() not being able to set the fde in the last trace.
    When this occurs the cfa of the trace will be behind of context's cfa.
    Also, libgo<E2><80><99>s probestackmaps() calls the backtrace with a null
po
    and can get to the backchain fallback with the same problem, in this case
    we are only interested in find a stack map, we don't need nor can do a
    backchain.
    _Unwind_ForcedUnwind_Phase2() can hit the same issue as it uses
    uw_frame_state_for(), so we need to treat _URC_NORMAL_STOP.

    libgcc/ChangeLog:
        PR libgcc/103044
        * config/rs6000/linux-unwind.h (ppc_backchain_fallback): Check if it's
        called with a null argument or at the end of the backtrace and return.
        * unwind.inc (_Unwind_ForcedUnwind_Phase2): Treat _URC_NORMAL_STOP.

[Bug libgcc/103004] [12 regression] r12-4416 breaks backtrace on PPC64 Big-endian

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103004

Segher Boessenkool <segher at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |FIXED

--- Comment #6 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Fixed.