https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103602
Bug ID: 103602
Summary: [11 regression] Analyzer takes inadequate amount of
memory and time linking GNU grep with LTO
Product: gcc
Version: 11.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: analyzer
Assignee: dmalcolm at gcc dot gnu.org
Reporter: glebfm at altlinux dot org
Target Milestone: ---
$ gcc --version
x86_64-alt-linux-gcc (GCC) 11.2.1 20211202 (ALT Sisyphus 11.2.1-alt2)
Copyright (C) 2021 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
$ git clone https://git.savannah.gnu.org/git/grep.git && cd grep && ./bootstrap
&& CFLAGS='-g -O2 -flto=auto -Wno-error' ./configure && /usr/bin/time make
-j`nproc`
...
178.93user 6.85system 2:56.67elapsed 105%CPU (0avgtext+0avgdata
7943640maxresident)k
0inputs+0outputs (0major+2626777minor)pagefaults 0swaps
$ cd src && /usr/bin/time gcc -fanalyzer -fno-common -Wall -Warith-conversion
-Wbad-function-cast -Wcast-align=strict -Wdate-time -Wdisabled-optimization
-Wdouble-promotion -Wduplicated-branches -Wduplicated-cond -Wextra
-Wformat-signedness -Winit-self -Winvalid-pch -Wlogical-op
-Wmissing-declarations -Wmissing-include-dirs -Wmissing-prototypes
-Wnested-externs -Wnull-dereference -Wold-style-definition -Wopenmp-simd
-Woverlength-strings -Wpacked -Wpointer-arith -Wshadow -Wstrict-prototypes
-Wsuggest-attribute=cold -Wsuggest-attribute=const -Wsuggest-attribute=format
-Wsuggest-attribute=malloc -Wsuggest-attribute=noreturn
-Wsuggest-attribute=pure -Wsuggest-final-methods -Wsuggest-final-types
-Wsync-nand -Wtrampolines -Wuninitialized -Wunknown-pragmas -Wunused-macros
-Wvariadic-macros -Wvector-operation-performance -Wvla -Wwrite-strings
-Warray-bounds=2 -Wattribute-alias=2 -Wformat-overflow=2 -Wformat=2
-Wformat-truncation=2 -Wimplicit-fallthrough=5 -Wshift-overflow=2
-Wunused-const-variable=2 -Wvla-larger-than=4031 -Wno-analyzer-malloc-leak
-Wno-missing-field-initializers -Wno-sign-compare -Wno-unused-parameter
-Wno-cast-function-type -Wno-logical-op -Wno-format-nonliteral -Werror -g -O2
-flto=auto -Wno-error -o grep dfasearch.o grep.o kwsearch.o kwset.o
searchutils.o ../lib/libgreputils.a ../lib/libgreputils.a
...
175.29user 2.75system 2:56.95elapsed 100%CPU (0avgtext+0avgdata
7934612maxresident)k
0inputs+0outputs (0major+2050508minor)pagefaults 0swaps
(with -fno-analyzer flag)
$ git clone https://git.savannah.gnu.org/git/grep.git && cd grep && ./bootstrap
&& CFLAGS='-g -O2 -flto=auto -fno-analyzer -Wno-error' ./configure &&
/usr/bin/time make -j`nproc`
...
7.53user 5.04system 0:02.66elapsed 471%CPU (0avgtext+0avgdata
65336maxresident)k
0inputs+0outputs (0major+642146minor)pagefaults 0swaps
$ cd src && /usr/bin/time gcc -fanalyzer -fno-common -Wall -Warith-conversion
-Wbad-function-cast -Wcast-align=strict -Wdate-time -Wdisabled-optimization
-Wdouble-promotion -Wduplicated-branches -Wduplicated-cond -Wextra
-Wformat-signedness -Winit-self -Winvalid-pch -Wlogical-op
-Wmissing-declarations -Wmissing-include-dirs -Wmissing-prototypes
-Wnested-externs -Wnull-dereference -Wold-style-definition -Wopenmp-simd
-Woverlength-strings -Wpacked -Wpointer-arith -Wshadow -Wstrict-prototypes
-Wsuggest-attribute=cold -Wsuggest-attribute=const -Wsuggest-attribute=format
-Wsuggest-attribute=malloc -Wsuggest-attribute=noreturn
-Wsuggest-attribute=pure -Wsuggest-final-methods -Wsuggest-final-types
-Wsync-nand -Wtrampolines -Wuninitialized -Wunknown-pragmas -Wunused-macros
-Wvariadic-macros -Wvector-operation-performance -Wvla -Wwrite-strings
-Warray-bounds=2 -Wattribute-alias=2 -Wformat-overflow=2 -Wformat=2
-Wformat-truncation=2 -Wimplicit-fallthrough=5 -Wshift-overflow=2
-Wunused-const-variable=2 -Wvla-larger-than=4031 -Wno-analyzer-malloc-leak
-Wno-missing-field-initializers -Wno-sign-compare -Wno-unused-parameter
-Wno-cast-function-type -Wno-logical-op -Wno-format-nonliteral -Werror -g -O2
-flto=auto -fno-analyzer -Wno-error -o grep dfasearch.o grep.o kwsearch.o
kwset.o searchutils.o ../lib/libgreputils.a ../lib/libgreputils.a
...
3.31user 0.13system 0:02.33elapsed 147%CPU (0avgtext+0avgdata
65600maxresident)k
0inputs+0outputs (0major+69122minor)pagefaults 0swaps
I bisected this issue to commit r12-1389-g9d20ec97475 (backport
r11-8680-gf018044145e in releases/gcc-11 branch), after this change analyzer
consumes 3 times more memory (2.5G -> 7.5G) to analyze grep.
