From a64751019f3eab8a7d6d678ad76fdb8c31b86e54 Mon Sep 17 00:00:00 2001 From: Tom Eccles Date: Mon, 12 May 2025 09:38:01 +0000 Subject: [PATCH 1/2] [flang][OpenMP][Semantics] resolve objects in the flush arg list Fixes #136583 Normally the flush argument list would contain a DataRef to some variable. All DataRefs are handled generically in resolve-names and so the problem wasn't observed. But when a common block name is specified, this is not parsed as a DataRef. There was already handling in resolve-directives for OmpObjectList but not for argument lists. I've added a visitor for FLUSH which ensures all of the arguments have been resolved. The test is there to make sure the compiler doesn't crashed encountering the unresolved symbol. It shows that we currently deny flushing a common block. I'm not sure that it is right to restrict common blocks from flush argument lists, but fixing that can come in a different patch. This one is fixing an ICE. --- flang/lib/Semantics/resolve-directives.cpp | 13 +++++++++++++ flang/test/Semantics/OpenMP/flush04.f90 | 11 +++++++++++ 2 files changed, 24 insertions(+) create mode 100644 flang/test/Semantics/OpenMP/flush04.f90 diff --git a/flang/lib/Semantics/resolve-directives.cpp b/flang/lib/Semantics/resolve-directives.cpp index 8b1caca34a6a7..68f8cf9f17620 100644 --- a/flang/lib/Semantics/resolve-directives.cpp +++ b/flang/lib/Semantics/resolve-directives.cpp @@ -409,6 +409,19 @@ class OmpAttributeVisitor : DirectiveAttributeVisitor { } void Post(const parser::OpenMPDepobjConstruct &) { PopContext(); } + bool Pre(const parser::OpenMPFlushConstruct &x) { + PushContext(x.source, llvm::omp::Directive::OMPD_flush); + for (auto &arg : x.v.Arguments().v) { + if (auto *locator{std::get_if(&arg.u)}) { + if (auto *object{std::get_if(&locator->u)}) { + ResolveOmpObject(*object, Symbol::Flag::OmpDependObject); + } + } + } + return true; + } + void Post(const parser::OpenMPFlushConstruct &) { PopContext(); } + bool Pre(const parser::OpenMPRequiresConstruct &x) { using Flags = WithOmpDeclarative::RequiresFlags; using Requires = WithOmpDeclarative::RequiresFlag; diff --git a/flang/test/Semantics/OpenMP/flush04.f90 b/flang/test/Semantics/OpenMP/flush04.f90 new file mode 100644 index 0000000000000..ffc2273b692dc --- /dev/null +++ b/flang/test/Semantics/OpenMP/flush04.f90 @@ -0,0 +1,11 @@ +! RUN: %python %S/../test_errors.py %s %flang_fc1 -fopenmp + +! Regression test to ensure that the name /c/ in the flush argument list is +! resolved to the common block symbol. + + common /c/ x + real :: x +!ERROR: FLUSH argument must be a variable list item + !$omp flush(/c/) +end + From d25c9fda4cd19bd9a27f4056c2baf5eaa9dd7d37 Mon Sep 17 00:00:00 2001 From: Tom Eccles Date: Mon, 12 May 2025 16:05:36 +0000 Subject: [PATCH 2/2] Respond to review feedback --- flang/lib/Semantics/resolve-directives.cpp | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/flang/lib/Semantics/resolve-directives.cpp b/flang/lib/Semantics/resolve-directives.cpp index 68f8cf9f17620..e34c48c1983ca 100644 --- a/flang/lib/Semantics/resolve-directives.cpp +++ b/flang/lib/Semantics/resolve-directives.cpp @@ -414,7 +414,14 @@ class OmpAttributeVisitor : DirectiveAttributeVisitor { for (auto &arg : x.v.Arguments().v) { if (auto *locator{std::get_if(&arg.u)}) { if (auto *object{std::get_if(&locator->u)}) { - ResolveOmpObject(*object, Symbol::Flag::OmpDependObject); + if (auto *name{std::get_if(&object->u)}) { + // ResolveOmpCommonBlockName resolves the symbol as a side effect + if (!ResolveOmpCommonBlockName(name)) { + context_.Say(name->source, // 2.15.3 + "COMMON block must be declared in the same scoping unit " + "in which the OpenMP directive or clause appears"_err_en_US); + } + } } } }