Hello,
The new gcc.dg/lto/pr80922 test appears to fail for all arm-none-eabi targets:
Testing gcc.dg/lto/pr80922-2, -O0 -flto -flto-partition=none -fuse-linker-plugin
doing compile
Executing on host: /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
-mthumb -march=armv6s-m -mcpu=cortex-m0 -mfloat-abi=soft -mfpu=auto
-fdiagnostics-plain-output -O0 -flto -flto-partition=none -fuse-linker-plugin
-O2 -Wfree-nonheap-object -c -o c_lto_pr80922-2_0.o
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_0.c (timeout = 800)
spawn -ignore SIGHUP /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
-mthumb -march=armv6s-m -mcpu=cortex-m0 -mfloat-abi=soft -mfpu=auto
-fdiagnostics-plain-output -O0 -flto -flto-partition=none -fuse-linker-plugin
-O2 -Wfree-nonheap-object -c -o c_lto_pr80922-2_0.o
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_0.c
pid is 703324 -703324
pid is -1
output is status 0
PASS: gcc.dg/lto/pr80922-2 c_lto_pr80922-2_0.o assemble, -O0 -flto
-flto-partition=none -fuse-linker-plugin
doing compile
Executing on host: /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
-mthumb -march=armv6s-m -mcpu=cortex-m0 -mfloat-abi=soft -mfpu=auto
-fdiagnostics-plain-output -O0 -flto -flto-partition=none -fuse-linker-plugin
-O2 -Wfree-nonheap-object -c -o c_lto_pr80922-2_1.o
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_1.c (timeout = 800)
spawn -ignore SIGHUP /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
-mthumb -march=armv6s-m -mcpu=cortex-m0 -mfloat-abi=soft -mfpu=auto
-fdiagnostics-plain-output -O0 -flto -flto-partition=none -fuse-linker-plugin
-O2 -Wfree-nonheap-object -c -o c_lto_pr80922-2_1.o
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_1.c
pid is 703370 -703370
pid is -1
output is status 0
PASS: gcc.dg/lto/pr80922-2 c_lto_pr80922-2_1.o assemble, -O0 -flto
-flto-partition=none -fuse-linker-plugin
doing compile
Executing on host: /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
-mthumb -march=armv6s-m -mcpu=cortex-m0 -mfloat-abi=soft -mfpu=auto
-fdiagnostics-plain-output -O0 -flto -flto-partition=none -fuse-linker-plugin
-O2 -Wfree-nonheap-object -c -o c_lto_pr80922-2_2.o
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_2.c (timeout = 800)
spawn -ignore SIGHUP /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
-mthumb -march=armv6s-m -mcpu=cortex-m0 -mfloat-abi=soft -mfpu=auto
-fdiagnostics-plain-output -O0 -flto -flto-partition=none -fuse-linker-plugin
-O2 -Wfree-nonheap-object -c -o c_lto_pr80922-2_2.o
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_2.c
pid is 703406 -703406
pid is -1
output is status 0
PASS: gcc.dg/lto/pr80922-2 c_lto_pr80922-2_2.o assemble, -O0 -flto
-flto-partition=none -fuse-linker-plugin
doing compile
Executing on host: /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
c_lto_pr80922-2_1.o c_lto_pr80922-2_2.o -mthumb -march=armv6s-m -mcpu=cortex-m0
-mfloat-abi=soft -mfpu=auto -dumpbase "" -fdiagnostics-plain-output -r
--specs=rdimon.specs -Wl,--start-group -lc -lm -Wl,--end-group --specs=nosys.specs
-Wl,--allow-multiple-definition -Wl,-u,_isatty,-u,_fstat -Wl,-wrap,exit -Wl,-wrap,_exit
-Wl,-wrap,main -Wl,-wrap,abort -Wl,gcc_tg.o -o c_lto_pr80922-2.o (timeout = 800)
spawn -ignore SIGHUP /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
c_lto_pr80922-2_1.o c_lto_pr80922-2_2.o -mthumb -march=armv6s-m -mcpu=cortex-m0
-mfloat-abi=soft -mfpu=auto -dumpbase -fdiagnostics-plain-output -r
--specs=rdimon.specs -Wl,--start-group -lc -lm -Wl,--end-group
--specs=nosys.specs -Wl,--allow-multiple-definition -Wl,-u,_isatty,-u,_fstat
-Wl,-wrap,exit -Wl,-wrap,_exit -Wl,-wrap,main -Wl,-wrap,abort -Wl,gcc_tg.o -o
c_lto_pr80922-2.o
pid is 703440 -703440
/build/r17-2833-g32657f29f91871/arm-none-eabi/bin/ld: warning: incremental
linking of LTO and non-LTO objects; using -flinker-output=nolto-rel which will
bypass whole program optimization
In function 'myfree2',
inlined from 'main' at
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c:8:3:
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_1.c:5:3: warning:
'__builtin_free' called on unallocated object 'a' [-Wfree-nonheap-object]
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c: In function 'main':
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c:4:13: note: declared here
In function 'myfree2',
inlined from 'main' at
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c:8:3:
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_1.c:10:3: warning:
'__builtin_free' called on unallocated object 'c' [-Wfree-nonheap-object]
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c: In function 'main':
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c:4:19: note: declared here
pid is -1
output is /build/r17-2833-g32657f29f91871/arm-none-eabi/bin/ld: warning:
incremental linking of LTO and non-LTO objects; using -flinker-output=nolto-rel
which will bypass whole program optimization
In function 'myfree2',
inlined from 'main' at
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c:8:3:
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_1.c:5:3: warning:
'__builtin_free' called on unallocated object 'a' [-Wfree-nonheap-object]
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c: In function 'main':
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c:4:13: note: declared here
In function 'myfree2',
inlined from 'main' at
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c:8:3:
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-2_1.c:10:3: warning:
'__builtin_free' called on unallocated object 'c' [-Wfree-nonheap-object]
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c: In function 'main':
/build/gcc_src/gcc/testsuite/gcc.dg/lto/pr80922-1_1.c:4:19: note: declared here
status 0
FAIL: gcc.dg/lto/pr80922-2 c_lto_pr80922-2_2.o-c_lto_pr80922-2_2.o link,
incr-link
doing compile
Executing on host: /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
c_lto_pr80922-2_0.o c_lto_pr80922-2.o -mthumb -march=armv6s-m -mcpu=cortex-m0
-mfloat-abi=soft -mfpu=auto -dumpbase "" -fdiagnostics-plain-output -O0
-flto -flto-partition=none -fuse-linker-plugin -O2 -Wfree-nonheap-object
--specs=rdimon.specs -Wl,--start-group -lc -lm -Wl,--end-group --specs=nosys.specs
-Wl,--allow-multiple-definition -Wl,-u,_isatty,-u,_fstat -Wl,-wrap,exit -Wl,-wrap,_exit
-Wl,-wrap,main -Wl,-wrap,abort -Wl,gcc_tg.o -T qemu.ld -o gcc-dg-lto-pr80922-2-01.exe
(timeout = 800)
spawn -ignore SIGHUP /build/r17-2833-g32657f29f91871/bin/arm-none-eabi-gcc
c_lto_pr80922-2_0.o c_lto_pr80922-2.o -mthumb -march=armv6s-m -mcpu=cortex-m0
-mfloat-abi=soft -mfpu=auto -dumpbase -fdiagnostics-plain-output -O0 -flto
-flto-partition=none -fuse-linker-plugin -O2 -Wfree-nonheap-object
--specs=rdimon.specs -Wl,--start-group -lc -lm -Wl,--end-group
--specs=nosys.specs -Wl,--allow-multiple-definition -Wl,-u,_isatty,-u,_fstat
-Wl,-wrap,exit -Wl,-wrap,_exit -Wl,-wrap,main -Wl,-wrap,abort -Wl,gcc_tg.o -T
qemu.ld -o gcc-dg-lto-pr80922-2-01.exe
pid is 703533 -703533
pid is -1
output is status 0
FAIL: gcc.dg/lto/pr80922-2 (test for LTO warnings, pr80922-2_0.c line 10 -O0
-flto -flto-partition=none -fuse-linker-plugin)
FAIL: gcc.dg/lto/pr80922-2 (test for LTO warnings, pr80922-2_0.c line 15 -O0
-flto -flto-partition=none -fuse-linker-plugin)
FAIL: gcc.dg/lto/pr80922-2 (test for LTO warnings, pr80922-2_1.c line 5 -O0
-flto -flto-partition=none -fuse-linker-plugin)
FAIL: gcc.dg/lto/pr80922-2 (test for LTO warnings, pr80922-2_1.c line 10 -O0
-flto -flto-partition=none -fuse-linker-plugin)
PASS: gcc.dg/lto/pr80922-2 c_lto_pr80922-2_0.o-c_lto_pr80922-2.o link, -O0
-flto -flto-partition=none -fuse-linker-plugin
Kind regards,
Torbjörn
On 2026-07-09 03:17, Lewis Hyatt wrote:
Ok, this is looks reasonable.
As possible (future) improvement, would it not be better to output one hash
per symtab_node?
Not sure whether locations can appear somewhere without being an
undividable part of symtab_node/toplevel_node.
During WPA, function sections get copied from the input to the output
files without being read, so I thought it might be safer to guarantee
each section is individually OK on its own as well. But I'm happy to
look into this further sometime. Perhaps also a single SHA1 hash of
all relevant maps for each of the sections containing locations would
be more efficient too.
Thank you both for reviewing these. I am planning to commit the
patches this weekend absent any other comments.
-Lewis
