[Flang][Parser] Add missing dependencies to CMakeLists.txt

[kparzysz]

Two additional component libraries: FrontendOpenACC and FrontendOpenMP.

[llvmbot]

@llvm/pr-subscribers-flang-parser

@llvm/pr-subscribers-flang-fir-hlfir

Author: Krzysztof Parzyszek (kparzysz)

Changes

Two additional component libraries: FrontendOpenACC and FrontendOpenMP.

---

Full diff: https://github.com/llvm/llvm-project/pull/77483.diff

1 Files Affected:

• (modified) flang/lib/Lower/CMakeLists.txt (+2)

diff --git a/flang/lib/Lower/CMakeLists.txt b/flang/lib/Lower/CMakeLists.txt
index b13d415e02f1d9..8183d4280c2597 100644
--- a/flang/lib/Lower/CMakeLists.txt
+++ b/flang/lib/Lower/CMakeLists.txt
@@ -56,5 +56,7 @@ add_flang_library(FortranLower
   MLIRSCFToControlFlow
 
   LINK_COMPONENTS
+  FrontendOpenACC
+  FrontendOpenMP
   Support
 )

[kparzysz]

This is needed for getting directive names for both OpenMP and OpenACC when using DumpTree from the AST dumper.

[kiranchandramohan]

This is needed for getting directive names for both OpenMP and OpenACC when using DumpTree from the AST dumper.

I see that FortranParser has a link_component entry for FrontendOpenACC, is it enough to add an entry for FrontendOpenMP there?

add_flang_library(FortranParser
  Fortran-parsers.cpp
  ...

  LINK_LIBS
  FortranCommon

  LINK_COMPONENTS
  Support
  FrontendOpenACC

  DEPENDS
  omp_gen
  acc_gen
)

[clementval]

This is needed for getting directive names for both OpenMP and OpenACC when using DumpTree from the AST dumper.

DumpTree is not part of Lowering libs. I guess @kiranchandramohan suggestion should work for DumpTree.

[kparzysz]

Sounds good. Will update the PR later today.

[kiranchandramohan]

LGTM.

[kparzysz]

Bad news, this didn't work. I put DumpTree in OpenMP.cpp, and I'm getting

/usr/bin/ld: CMakeFiles/obj.FortranLower.dir/OpenMP.cpp.o: in function `std::enable_if<((!(is_class_v<llvm::acc::Directive>))||(is_same_v<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, llvm::acc::Directive>))||(is_same_v<Fortran::parser::CharBlock, llvm::acc::Directive>), void>::type Fortran::parser::Walk<llvm::acc::Directive, Fortran::parser::ParseTreeDumper>(llvm::acc::Directive const&, Fortran::parser::ParseTreeDumper&)':
OpenMP.cpp:(.text._ZN7Fortran6parser4WalkIN4llvm3acc9DirectiveENS0_15ParseTreeDumperEEENSt9enable_ifIXoooont10is_class_vIT_E9is_same_vINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES7_E9is_same_vINS0_9CharBlockES7_EEvE4typeERKS7_RT0_[_ZN7Fortran6parser4WalkIN4llvm3acc9DirectiveENS0_15ParseTreeDumperEEENSt9enable_ifIXoooont10is_class_vIT_E9is_same_vINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES7_E9is_same_vINS0_9CharBlockES7_EEvE4typeERKS7_RT0_]+0x146): undefined reference to `llvm::acc::getOpenACCDirectiveName(llvm::acc::Directive)'
/usr/bin/ld: CMakeFiles/obj.FortranLower.dir/OpenMP.cpp.o: in function `std::enable_if<WrapperTrait<Fortran::parser::AccDefaultClause>, void>::type Fortran::parser::Walk<Fortran::parser::AccDefaultClause, Fortran::parser::ParseTreeDumper>(Fortran::parser::AccDefaultClause const&, Fortran::parser::ParseTreeDumper&)':
OpenMP.cpp:(.text._ZN7Fortran6parser4WalkINS0_16AccDefaultClauseENS0_15ParseTreeDumperEEENSt9enable_ifIX12WrapperTraitIT_EEvE4typeERKS5_RT0_[_ZN7Fortran6parser4WalkINS0_16AccDefaultClauseENS0_15ParseTreeDumperEEENSt9enable_ifIX12WrapperTraitIT_EEvE4typeERKS5_RT0_]+0x27c): undefined reference to `llvm::acc::getOpenACCDefaultValueName(llvm::acc::DefaultValue)'
collect2: error: ld returned 1 exit status```

[clementval]

Why would you put DumpTree in lowering? For local debugging?

[kparzysz]

Why would you put DumpTree in lowering? For local debugging?

Basically, yes. I can add these libraries when I need them, so this is not a big deal. I should probably revert this commit though, since it doesn't accomplish anything.

[kparzysz]

Although... If I don't need to link any extra libraries do get DumpTree, I'd expect it to just work.

[clementval]

Well DumpTree is not really meant to be called from lowering so I would not add the library unless there is an upstream usage of it.

[clementval]

FrontendOpenACC was added a while back to fix shared library dependencies https://reviews.llvm.org/D83938. I'm not sure why FrontendOpenMP was not added at the same time or if both are really needed.

[kparzysz]

When I looked at the "needed" libraries for libFortranParser.so, it still only showed the OpenACC one, even with the OpenMP library in CMakeLists.txt. I don't know why.

[clementval]

There are some usage of llvm::omp::getOpenMPDirectiveName in OpenMP.cpp so DumpTree should work for you. Do you build shared libraries or out of tree?

[kparzysz]

I build shared libraries. Looking again at the error messages---it seems like it's this symbol that's missing: llvm::acc::getOpenACCDirectiveName(llvm::acc::Directive).