12.0.0: polly is not LTO ready

[kloczek]

Bugzilla Link	50021
Resolution	FIXED
Resolved on	May 03, 2021 17:20
Version	unspecified
OS	Windows NT
Blocks	#48661
CC	@Meinersbur
Fixed by commit(s)	90e5ce0 89b5934 b8e4d4e 8b2c019

Extended Description

Looks like polly 12.0.0 is not LTO ready.
Below was reproduced using gcc 11.0.1 from fedora rawhide.

color=
make[2]: Leaving directory '/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu'
make -f lib/External/CMakeFiles/PollyPPCG.dir/build.make lib/External/CMakeFiles/PollyPPCG.dir/build
make[2]: Entering directory '/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu'
[ 88%] Linking C shared library libPollyPPCG.so
cd /home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu/lib/External && /usr/bin/cmake -E cmake_link_script CMakeFiles/PollyPPCG.dir/link.txt --verbose=1
/usr/bin/gcc -fPIC -O2 -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 -fdata-sections -ffunction-sections -flto=auto -flto-partition=none -fno-strict-aliasing -fPIC -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wimplicit-fallthrough -Wno-comment -ffunction-sections -fdata-sections -fPIC -DNDEBUG -Wl,-z,relro -Wl,--as-needed -Wl,--gc-sections -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -flto=auto -flto-partition=none -fuse-linker-plugin -Wl,-z,defs -Wl,-z,nodelete -shared -Wl,-soname,libPollyPPCG.so -o libPollyPPCG.so CMakeFiles/PollyPPCG.dir/ppcg/cuda.c.o CMakeFiles/PollyPPCG.dir/ppcg/cuda_common.c.o CMakeFiles/PollyPPCG.dir/ppcg/external.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_array_tile.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_group.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_hybrid.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_print.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_tree.c.o CMakeFiles/PollyPPCG.dir/ppcg/grouping.c.o CMakeFiles/PollyPPCG.dir/ppcg/hybrid.c.o CMakeFiles/PollyPPCG.dir/ppcg/ppcg.c.o CMakeFiles/PollyPPCG.dir/ppcg/ppcg_options.c.o CMakeFiles/PollyPPCG.dir/ppcg/print.c.o CMakeFiles/PollyPPCG.dir/ppcg/schedule.c.o CMakeFiles/PollyPPCG.dir/ppcg/util.c.o -Wl,-rpath,/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu/lib/External: libPollyISL.so
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/print.c:54:14: warning: type of ‘isl_id_alloc’ does not match original declaration [-Wlto-type-mismatch]
54 | id = isl_id_alloc(ctx, note_name, NULL);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:22:20: note: return value type mismatch
22 | __isl_give isl_id *isl_id_alloc(isl_ctx *ctx,
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:22:20: note: ‘isl_id_alloc’ was previously declared here
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:22:20: note: code may be misoptimized unless ‘-fno-strict-aliasing’ is used
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/print.c:164:29: warning: type of ‘isl_id_set_free_user’ does not match original declaration [-Wlto-type-mismatch]
164 | macros_id = isl_id_set_free_user(macros_id, &ppcg_macros_free);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:31:20: note: return value type mismatch
31 | __isl_give isl_id *isl_id_set_free_user(__isl_take isl_id *id,
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:31:20: note: ‘isl_id_set_free_user’ was previously declared here
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:31:20: note: code may be misoptimized unless ‘-fno-strict-aliasing’ is used
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/print.c:78:44: warning: type of ‘isl_id_copy’ does not match original declaration [-Wlto-type-mismatch]
78 | return isl_printer_set_note(p, id, isl_id_copy(id));
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:24:20: note: return value type mismatch
24 | __isl_give isl_id *isl_id_copy(isl_id *id);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:24:20: note: ‘isl_id_copy’ was previously declared here
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:24:20: note: code may be misoptimized unless ‘-fno-strict-aliasing’ is used
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/pet/include/pet.h:20:1: error: function ‘pet_options_args’ redeclared as variable
20 | ISL_ARG_DECL(pet_options, struct pet_options, pet_options_args)
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/external.c:107:6: note: previously declared here
107 | void pet_options_args() {
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/print.c:191:18: warning: type of ‘isl_id_get_user’ does not match original declaration [-Wlto-type-mismatc ]
191 | macros = isl_id_get_user(id);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:27:7: note: return value type mismatch
27 | void *isl_id_get_user(__isl_keep isl_id *id);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:27:7: note: ‘isl_id_get_user’ was previously declared here
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:27:7: note: code may be misoptimized unless ‘-fno-strict-aliasing’ is used
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/print.c:56:9: warning: type of ‘isl_id_free’ does not match original declaration [-Wlto-type-mismatch]
56 | isl_id_free(id);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:25:20: note: return value type mismatch
25 | __isl_null isl_id *isl_id_free(__isl_take isl_id *id);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:25:20: note: ‘isl_id_free’ was previously declared here
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/include/isl/id.h:25:20: note: code may be misoptimized unless ‘-fno-strict-aliasing’ is used
lto1: fatal error: errors during merging of translation units
compilation terminated.
lto-wrapper: fatal error: /usr/bin/gcc returned 1 exit status
compilation terminated.
/usr/bin/ld: error: lto-wrapper failed
collect2: error: ld returned 1 exit status
make[2]: *** [lib/External/CMakeFiles/PollyPPCG.dir/build.make:332: lib/External/libPollyPPCG.so] Error 1
make[2]: Target 'lib/External/CMakeFiles/PollyPPCG.dir/build' not remade because of errors.
make[2]: Leaving directory '/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu'
make[1]: *** [CMakeFiles/Makefile2:564: lib/External/CMakeFiles/PollyPPCG.dir/all] Error 2
make -f lib/External/CMakeFiles/polly-isl-test.dir/build.make lib/External/CMakeFiles/polly-isl-test.dir/depend
make[2]: Entering directory '/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu'
cd /home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu && /usr/bin/cmake -E cmake_depends "Unix Makefiles" /home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src /home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External /home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu /home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu/lib/External /home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu/lib/External/CMakeFiles/polly-isl-test.dir/DependInfo.cmake --color=
make[2]: Leaving directory '/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu'
make -f lib/External/CMakeFiles/polly-isl-test.dir/build.make lib/External/CMakeFiles/polly-isl-test.dir/build
make[2]: Entering directory '/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu'
make[2]: Nothing to be done for 'lib/External/CMakeFiles/polly-isl-test.dir/build'.
make[2]: Leaving directory '/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu'
[ 90%] Built target polly-isl-test
make[1]: Target 'all' not remade because of errors.
make[1]: Leaving directory '/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu'
make: *** [Makefile:152: all] Error 2
make: Target 'default_target' not remade because of errors.

cmake settings:

[tkloczko@barrel x86_64-redhat-linux-gnu]$ cmake -L
CMake Warning:
No source or binary directory provided. Both will be assumed to be the
same as the current working directory, but note that this warning will
become a fatal error in future CMake releases.

CMake Error: The source directory "/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu" does not appear to contain CMakeLists.txt.
Specify --help for usage, or press the help button on the CMake GUI.
-- Cache values
CMAKE_BUILD_TYPE:STRING=RelWithDebInfo
CMAKE_INSTALL_PREFIX:PATH=/usr
LLVM_DIR:PATH=/usr/lib64/cmake/llvm
LLVM_ENABLE_IDE:BOOL=OFF
LLVM_ENABLE_LTO:STRING=OFF
LLVM_EXPORT_SYMBOLS_FOR_PLUGINS:BOOL=OFF
LLVM_EXTERNAL_LIT:STRING=/usr/bin/lit
LLVM_FILECHECK:FILEPATH=/usr/bin/FileCheck
LLVM_FORCE_ENABLE_STATS:BOOL=OFF
LLVM_NOT:FILEPATH=/usr/bin/not
LLVM_OPT:FILEPATH=/usr/bin/opt
LLVM_PARALLEL_COMPILE_JOBS:STRING=
LLVM_PARALLEL_LINK_JOBS:STRING=
LLVM_POLLY_LINK_INTO_TOOLS:BOOL=OFF
LLVM_SOURCE_PREFIX:STRING=
LLVM_SOURCE_ROOT:PATH=/home/tkloczko/rpmbuild/BUILD/llvm-12.0.0.src
LLVM_USE_RELATIVE_PATHS_IN_DEBUG_INFO:BOOL=OFF
LLVM_USE_RELATIVE_PATHS_IN_FILES:BOOL=OFF
POLLY_BUNDLED_ISL:BOOL=ON
POLLY_ENABLE_GPGPU_CODEGEN:BOOL=OFF
SPHINX_EXECUTABLE:FILEPATH=/usr/bin/sphinx-build
SPHINX_OUTPUT_HTML:BOOL=ON
SPHINX_OUTPUT_MAN:BOOL=ON
SPHINX_WARNINGS_AS_ERRORS:BOOL=OFF

[Meinersbur]

Thank you for the report.

I think this is due to implicitly defined functions in ppcg/print.c. However, with POLLY_ENABLE_GPGPU_CODEGEN=OFF, libPollyPPCG.so is not needed. Possibly the Makefile make no difference in which libraries are actually needed and just builds all libraries in a subdirectory.

That's two problems that I can fix.

[kloczek]

Please let me know if you will have patch for that.
I'll be glad to test that before it will be merged in to master :)

[Meinersbur]

Fixed by 90e5ce0 (Avoid implicit function definitions).

Commit 6048d1d also stops PollyPPCG from being defined if POLLY_ENABLE_GPGPU_CODEGEN is OFF, so not even gmake would build it.

@​Tom Stellard: Only include 90e5ce0 for 12.0.1

[kloczek]

Just tested that patch and looks like now compiling fails

[ 90%] Linking C shared library libPollyPPCG.so
cd /home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu/lib/External && /usr/bin/cmake -E cmake_link_script CMakeFiles/PollyPPCG.dir/link.txt --verbose=1
/usr/bin/gcc -fPIC -O2 -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 -fdata-sections -ffunction-sections -flto=auto -flto-partition=none -fPIC -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wimplicit-fallthrough -Wno-comment -ffunction-sections -fdata-sections -fPIC -DNDEBUG -Wl,-z,relro -Wl,--as-needed -Wl,--gc-sections -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -flto=auto -flto-partition=none -fuse-linker-plugin -Wl,-z,defs -Wl,-z,nodelete -shared -Wl,-soname,libPollyPPCG.so -o libPollyPPCG.so CMakeFiles/PollyPPCG.dir/ppcg/cuda.c.o CMakeFiles/PollyPPCG.dir/ppcg/cuda_common.c.o CMakeFiles/PollyPPCG.dir/ppcg/external.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_array_tile.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_group.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_hybrid.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_print.c.o CMakeFiles/PollyPPCG.dir/ppcg/gpu_tree.c.o CMakeFiles/PollyPPCG.dir/ppcg/grouping.c.o CMakeFiles/PollyPPCG.dir/ppcg/hybrid.c.o CMakeFiles/PollyPPCG.dir/ppcg/ppcg.c.o CMakeFiles/PollyPPCG.dir/ppcg/ppcg_options.c.o CMakeFiles/PollyPPCG.dir/ppcg/print.c.o CMakeFiles/PollyPPCG.dir/ppcg/schedule.c.o CMakeFiles/PollyPPCG.dir/ppcg/util.c.o -Wl,-rpath,/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/x86_64-redhat-linux-gnu/lib/External: libPollyISL.so
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/pet/include/pet.h:20:1: error: function ‘pet_options_args’ redeclared as variable
20 | ISL_ARG_DECL(pet_options, struct pet_options, pet_options_args)
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/external.c:107:6: note: previously declared here
107 | void pet_options_args() {
| ^
lto1: fatal error: errors during merging of translation units
compilation terminated.
lto-wrapper: fatal error: /usr/bin/gcc returned 1 exit status

[Meinersbur]

Thanks for the report. I committed a fix in 89b5934.

I also compiled Polly with -flto=auto myself to ensure that there no remaining issues. 'opt' and 'clang' compile successfully, but there seem to be remaining problems with LLVM itself, since check-llvm (and check-polly) does fail for every unit test with the following (+ many warnings):

/home/meinersbur/src/llvm-project/llvm/lib/Support/TimeProfiler.cpp:36:45: error: only zero initializers are allowed in section ‘.tbss._ZL25TimeTraceProfilerInstance.lto_priv.9719’
static LLVM_THREAD_LOCAL TimeTraceProfiler *TimeTraceProfilerInstance = nullptr;

However, it's not a Polly issue.

@​Tom Stellard: Please add 90e5ce0 and 89b5934 for 12.0.1

[kloczek]

With second patch I was able sucessfully build my rpm package with polly :)

Thx.

BTW LTO. Usimg gcc 11.0.1 looks like it exposes some new issues about initialisation of some variables.

/home/tkloczko/rpmbuild/BUILD/llvm-12.0.0.src/utils/unittest/googletest/src/gtest-death-test.cc: In function 'StackGrowsDown':
/home/tkloczko/rpmbuild/BUILD/llvm-12.0.0.src/utils/unittest/googletest/src/gtest-death-test.cc:1009:24: warning: 'dummy' may be used uninitialized [-Wmaybe-uninitialized]
1009 | StackLowerThanAddress(&dummy, &result);
| ^
/home/tkloczko/rpmbuild/BUILD/llvm-12.0.0.src/utils/unittest/googletest/src/gtest-death-test.cc:999:6: note: by argument 1 of type 'const void ' to 'StackLowerThanAddress' declared here
999 | void StackLowerThanAddress(const void ptr, bool* result) {
| ^
/home/tkloczko/rpmbuild/BUILD/llvm-12.0.0.src/utils/unittest/googletest/src/gtest-death-test.cc:1007:7: note: 'dummy' declared here
1007 | int dummy;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_ast.c: In function 'isl_ast_expr_dup':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_ast.c:189:24: warning: 'dup' may be used uninitialized in this function [-Wmaybe-uninitialized]
189 | return NULL;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_schedule_tree.c: In function 'initial_domain':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_schedule_tree.c:1942:24: warning: 'domain' may be used uninitialized in this function [-Wmaybe-uninitialized]
1942 | isl_union_set *domain;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_tab.c: In function 'isl_tab_add_ineq':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_int_sioimath.h:580:14: warning: 'MEM[(isl_sioimath *)&cst]' may be used uninitialized in this function -Wmaybe-uninitialized]
580 | *lhs = *rhs;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_tab.c:1900:17: note: 'MEM[(isl_sioimath *)&cst]' was declared here
1900 | isl_int cst;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_tab.c: In function 'isl_tab_add_eq':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_int_sioimath.h:580:14: warning: 'MEM[(isl_sioimath *)&cst]' may be used uninitialized in this function -Wmaybe-uninitialized]
580 | *lhs = *rhs;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_tab.c:2115:17: note: 'MEM[(isl_sioimath *)&cst]' was declared here
2115 | isl_int cst;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_schedule_tree.c: In function 'subtree_schedule_extend':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_schedule_tree.c:1836:24: warning: 'umap' may be used uninitialized in this function [-Wmaybe-uninitialized]
1836 | isl_union_map *umap;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_schedule_tree.c: In function 'isl_schedule_tree_plain_is_equal':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_schedule_tree.c:683:12: warning: 'equal' may be used uninitialized in this function [-Wmaybe-uninitialized]
683 | if (equal < 0 || !equal)
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_simplify.c: In function 'isl_basic_map_drop_redundant_divs_ineq':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_simplify.c:4759:12: warning: 'last_neg' may be used uninitialized in this function [-Wmaybe-uninitialized]
4759 | if (ineq1 > ineq2) {
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_simplify.c:5031:31: note: 'last_neg' was declared here
5031 | int last_pos, last_neg;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_simplify.c:4745:9: warning: 'last_pos' may be used uninitialized in this function [-Wmaybe-uninitialized]
4745 | isl_basic_map_inequality_to_equality(bmap, ineq);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_simplify.c:5031:21: note: 'last_pos' was declared here
5031 | int last_pos, last_neg;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/basis_reduction_templ.c: In function 'isl_tab_compute_reduced_basis':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/basis_reduction_templ.c:57:13: warning: 'row' may be used uninitialized in this function [-Wmaybe-uninitialized]
57 | int row;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_sample.c: In function 'isl_set_sample_point':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_sample.c:1331:16: warning: 'pnt' may be used uninitialized in this function [-Wmaybe-uninitialized]
1331 | return pnt;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_ast_build.c: In function 'isl_ast_build_insert_dim':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_ast_build.c:1556:17: warning: 'space' may be used uninitialized in this function [-Wmaybe-uninitialized]
1556 | space = isl_space_map_from_set(space);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_ast_build.c:1646:20: note: 'space' was declared here
1646 | isl_space *space, *ma_space;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_lexopt_templ.c: In function 'basic_map_partial_lexopt_pw_multi_aff':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_lexopt_templ.c:126:37: warning: 'all_empty' may be used uninitialized in this function [-Wmaybe-uninitialized]
126 | all_empty = isl_set_union_disjoint(all_empty, *empty);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_lexopt_templ.c:92:18: note: 'all_empty' was declared here
92 | isl_set *all_empty;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_scheduler.c: In function 'compute_schedule_wcc':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_scheduler.c:6089:64: warning: 'best_dist' may be used uninitialized in this function [-Wmaybe-uninitialized]
6089 | if (best_weight == weight && best_dist <= dist)
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_scheduler.c:6064:38: note: 'best_dist' was declared here
6064 | int i, best = graph->n_edge, best_dist, best_weight;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_scheduler.c:6089:41: warning: 'best_weight' may be used uninitialized in this function [-Wmaybe-uninitialized]
6089 | if (best_weight == weight && best_dist <= dist)
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_scheduler.c:6064:49: note: 'best_weight' was declared here
6064 | int i, best = graph->n_edge, best_dist, best_weight;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map.c: In function 'isl_map_partial_lexopt_aligned_pw_multi_aff':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map.c:7169:32: warning: 'todo' may be used uninitialized in this function [-Wmaybe-uninitialized]
7169 | todo = isl_set_intersect(todo, *empty);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map.c:7136:18: note: 'todo' was declared here
7136 | isl_set *todo;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map.c: In function 'isl_map_partial_lexopt_aligned':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_lexopt_templ.c:126:37: warning: 'all_empty' may be used uninitialized in this function [-Wmaybe-uninitialized]
126 | all_empty = isl_set_union_disjoint(all_empty, *empty);
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_map_lexopt_templ.c:92:18: note: 'all_empty' was declared here
92 | isl_set *all_empty;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/gpu_group.c: In function 'compute_group_bounds':
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/gpu_group.c:1129:41: warning: 'coalesced' may be used uninitialized in this function [-Wmaybe-uninitialize ]
1129 | if (use_shared && (!no_reuse || !coalesced)) {
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/ppcg/gpu_group.c:1097:23: note: 'coalesced' was declared here
1097 | int no_reuse, coalesced;
| ^
/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/docs/HowToManuallyUseTheIndividualPiecesOfPolly.rst:109: WARNING: Could not lex literal_block as "guess". Highlighting skipped.

[Meinersbur]

Google test and isl are both upstream projects. For isl, we disabled all warnings, so the warnings probably appears only because the linker plugin does not know about for which files this is the case.

Problems with upstream projects should be reported at the upstream project, at will eventually be updated in-tree. For isl, the author regularly considers compiler warnings a static analysers.

I looked at one the them and it's a false positive:

/home/tkloczko/rpmbuild/BUILD/polly-12.0.0.src/lib/External/isl/isl_int_sioimath.h:580:14: warning: 'MEM[(isl_sioimath *)&cst]' may be used uninitialized in this function -Wmaybe-uninitialized]

inline void isl_sioimath_swap(isl_sioimath_ptr lhs, isl_sioimath_ptr rhs)
{
isl_sioimath tmp = *lhs;
*lhs = *rhs;
*rhs = tmp;
}

isl_stat isl_tab_add_eq(struct isl_tab *tab, isl_int *eq)
{
isl_int cst;
[...]
if (tab->cone) {
isl_int_init(cst);
isl_int_set_si(cst, 0);
isl_int_swap(eq[0], cst);
}
r = isl_tab_add_row(tab, eq);
if (tab->cone) {
isl_int_swap(eq[0], cst);
isl_int_clear(cst);
}
[...]
}

If tab->cone is true, then cst will be initialized by isl_int_init(cst) before any of the swaps. My guess is that the warning does not consider that the conditions to the two branches are identical. Interestingly, this can only be diagnosed after inlining isl_int_swap, i.e. in an LTO pass.

[kloczek]

Maybe I'm wrong but I think that as visibility of those warnings has zero impact on generated code I think that better would be to not disable displaing of them.

[Meinersbur]

You are not wrong, but we are not maintaining these external projects. Like libxml2.so that LLVM links against. Since we do not make local changes, displaying them would just add noise. That many of them are false positives does not help wither. LLVM itself has a set of warnings it disables

[kloczek]

At the moment it is kind of discussion about libxml2 because maintainer of that project is kind of bottlenec.
https://gitlab.gnome.org/GNOME/libxml2/-/issues/186
Current state of the libxml2 hurts as well Gnome.
If situation will not change soon I can bet that someone from Gnome will take controll of libxml2 by forking it because current situation is not sustanable/acceptable.
Sometimes all wat needs to be done is speak with other people which want some changes :P
In other words if you have some issues with libxml just please drop some note in above ticket :)

Just please keep those warnigs visible as kind of recall that it is as well something to do outside of the LLVM :)

Nevertheless thank you very much for your time and help :)

[tstellar]

Merged: 8b2c019