On Mon, Aug 03, 2020 at 05:40:42PM +0200, Florian Weimer wrote:
* Daniel P. Berrangé:
> If I run LD_DEBUG=all on a build /with/ LTO, there are no symbol lookups
> at all for qemuProcessStartManagedPRDaemon. It looks very much like the
> call was resolved and bound at link time when built with LTO.
It's possible that the symbol extraction logic is confused by LTO, but
-ffat-lto-objects should prevent that.
Can you collect all the linker input scripts/command lines after libtool
has done its thing?
For the qemuhotplugtest, this should be the gcc line it is running:
gcc -DHAVE_CONFIG_H -I. -I../../tests -I.. -I.. -I../.. -I../include -I../../include
-I../src -I../../src -I../../src/util -I../../src/conf -I../../src/hypervisor -I../src/rpc
-Dabs_builddir="\"/builddir/build/BUILD/libvirt-6.5.0/x86_64-redhat-linux-gnu/tests\""
-Dabs_top_builddir="\"/builddir/build/BUILD/libvirt-6.5.0/x86_64-redhat-linux-gnu\""
-Dabs_srcdir="\"/builddir/build/BUILD/libvirt-6.5.0/x86_64-redhat-linux-gnu/../tests\""
-Dabs_top_srcdir="\"/builddir/build/BUILD/libvirt-6.5.0/x86_64-redhat-linux-gnu/..\""
-I/usr/include/libxml2 -I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include -pthread
-I/usr/include/libmount -I/usr/include/blkid -I/usr/include/libnl3 -I/usr/include/libnl3
-I/usr/include/p11-kit-1 -I/usr/include/tirpc -fno-common -W -Wabsolute-value
-Waddress -Waddress-of-packed-member -Waggressive-loop-optimizations -Wall
-Wattribute-warning -Wattributes -Wbool-compare -Wbool-operation
-Wbuiltin-declaration-mismatch -Wbuiltin-macro-redefined -Wcannot-profile -Wcast-align
-Wcast-align=strict -Wcast-function-type -Wchar-subscripts -Wclobbered -Wcomment
-Wcomments -Wcoverage-mismatch -Wcpp -Wdangling-else -Wdate-time -Wdeprecated-declarations
-Wdesignated-init -Wdiscarded-array-qualifiers -Wdiscarded-qualifiers -Wdiv-by-zero
-Wdouble-promotion -Wduplicated-cond -Wduplicate-decl-specifier -Wempty-body
-Wendif-labels -Wexpansion-to-defined -Wextra -Wformat-contains-nul -Wformat-extra-args
-Wformat-nonliteral -Wformat-security -Wformat-y2k -Wformat-zero-length -Wframe-address
-Wfree-nonheap-object -Whsa -Wif-not-aligned -Wignored-attributes -Wignored-qualifiers
-Wimplicit -Wimplicit-function-declaration -Wimplicit-int -Wincompatible-pointer-types
-Winit-self -Winline -Wint-conversion -Wint-in-bool-context -Wint-to-pointer-cast
-Winvalid-memory-model -Winvalid-pch -Wlogical-not-parentheses -Wlogical-op -Wmain
-Wmaybe-uninitialized -Wmemset-elt-size -Wmemset-transposed-args -Wmisleading-indentation
-Wmissing-attributes -Wmissing-braces -Wmissing-declarations -Wmissing-field-initializers
-Wmissing-include-dirs -Wmissing-parameter-type -Wmissing-profile -Wmissing-prototypes
-Wmultichar -Wmultistatement-macros -Wnarrowing -Wnested-externs -Wnonnull
-Wnonnull-compare -Wnull-dereference -Wodr -Wold-style-declaration -Wold-style-definition
-Wopenmp-simd -Woverflow -Woverride-init -Wpacked-bitfield-compat -Wpacked-not-aligned
-Wparentheses -Wpointer-arith -Wpointer-compare -Wpointer-sign -Wpointer-to-int-cast
-Wpragmas -Wpsabi -Wrestrict -Wreturn-local-addr -Wreturn-type -Wscalar-storage-order
-Wsequence-point -Wshadow -Wshift-count-negative -Wshift-count-overflow
-Wshift-negative-value -Wsizeof-array-argument -Wsizeof-pointer-div
-Wsizeof-pointer-memaccess -Wstrict-aliasing -Wstrict-prototypes -Wstringop-truncation
-Wsuggest-attribute=cold -Wsuggest-attribute=const -Wsuggest-attribute=format
-Wsuggest-attribute=noreturn -Wsuggest-attribute=pure -Wsuggest-final-methods
-Wsuggest-final-types -Wswitch -Wswitch-bool -Wswitch-unreachable -Wsync-nand
-Wtautological-compare -Wtrampolines -Wtrigraphs -Wtype-limits -Wuninitialized
-Wunknown-pragmas -Wunused -Wunused-but-set-parameter -Wunused-but-set-variable
-Wunused-function -Wunused-label -Wunused-local-typedefs -Wunused-parameter
-Wunused-result -Wunused-value -Wunused-variable -Wvarargs -Wvariadic-macros
-Wvector-operation-performance -Wvla -Wvolatile-register-var -Wwrite-strings
-Walloc-size-larger-than=9223372036854775807 -Warray-bounds=2 -Wattribute-alias=2
-Wformat-overflow=2 -Wformat-truncation=2 -Wimplicit-fallthrough=5 -Wnormalized=nfc
-Wshift-overflow=2 -Wstringop-overflow=2 -Wunused-const-variable=2 -Wvla-larger-than=4031
-Wno-sign-compare -Wno-cast-function-type -Wjump-misses-init -Wswitch-enum
-Wno-format-nonliteral -Wno-format-truncation -Wframe-larger-than=4096
-fstack-protector-strong -fexceptions -fasynchronous-unwind-tables -fipa-pure-const
-Wno-suggest-attribute=pure -Wno-suggest-attribute=const -std=gnu99
-Wframe-larger-than=262144 -O2 -flto=auto -ffat-lto-objects -fexceptions -g
-grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2
-Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1
-fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64
-mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -MT
qemuhotplugtest.o -MD -MP -MF $depbase.Tpo -c -o qemuhotplugtest.o
../../tests/qemuhotplugtest.c &&\
Taken from
https://koji.fedoraproject.org/koji/taskinfo?taskID=48525923
I can "fix" the probem by simply appending "-fno-lto" to this line
for
the qemuhotplugtest binary only.
I don't need to turn off LTO for any other parts of the build that this
links to, or preloads.
Regards,
Daniel
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