[Flang][OpenMP] Fix a crash for declare target in an interface

[kiranchandramohan]

This is a point fix for the crash in #116426. Leaving the bug open to further explore declare target issues for interfaces.

[llvmbot]

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

@llvm/pr-subscribers-flang-openmp

Author: Kiran Chandramohan (kiranchandramohan)

Changes

This is a point fix for the crash in #116426. Leaving the bug open to further explore declare target issues for interfaces.

---

Full diff: https://github.com/llvm/llvm-project/pull/117709.diff

2 Files Affected:

• (modified) flang/lib/Lower/OpenMP/OpenMP.cpp (+9-7)
• (added) flang/test/Lower/OpenMP/declare-target-interface.f90 (+11)

diff --git a/flang/lib/Lower/OpenMP/OpenMP.cpp b/flang/lib/Lower/OpenMP/OpenMP.cpp
index a2779213a1a15a..7afb7edc822101 100644
--- a/flang/lib/Lower/OpenMP/OpenMP.cpp
+++ b/flang/lib/Lower/OpenMP/OpenMP.cpp
@@ -487,13 +487,15 @@ static void getDeclareTargetInfo(
   } else if (const auto *clauseList{
                  parser::Unwrap<parser::OmpClauseList>(spec.u)}) {
     List<Clause> clauses = makeClauses(*clauseList, semaCtx);
-    if (clauses.empty() &&
-        (!eval.getOwningProcedure()->isMainProgram() ||
-         eval.getOwningProcedure()->getMainProgramSymbol())) {
-      // Case: declare target, implicit capture of function
-      symbolAndClause.emplace_back(
-          mlir::omp::DeclareTargetCaptureClause::to,
-          eval.getOwningProcedure()->getSubprogramSymbol());
+    if (clauses.empty()) {
+      Fortran::lower::pft::FunctionLikeUnit *owningProc =
+          eval.getOwningProcedure();
+      if (owningProc && (!owningProc->isMainProgram() ||
+                         owningProc->getMainProgramSymbol())) {
+        // Case: declare target, implicit capture of function
+        symbolAndClause.emplace_back(mlir::omp::DeclareTargetCaptureClause::to,
+                                     owningProc->getSubprogramSymbol());
+      }
     }
 
     ClauseProcessor cp(converter, semaCtx, clauses);
diff --git a/flang/test/Lower/OpenMP/declare-target-interface.f90 b/flang/test/Lower/OpenMP/declare-target-interface.f90
new file mode 100644
index 00000000000000..e92d1905c7ad05
--- /dev/null
+++ b/flang/test/Lower/OpenMP/declare-target-interface.f90
@@ -0,0 +1,11 @@
+!RUN: %flang_fc1 -emit-hlfir -fopenmp %s -o - | FileCheck %s
+!RUN: %flang_fc1 -emit-hlfir -fopenmp -fopenmp-is-device %s -o - | FileCheck %s
+
+!CHECK: module attributes
+module iface
+interface
+  subroutine a()
+  !$omp declare target
+  end subroutine
+end interface
+end module

[agozillon]

LGTM, thank you very much for the fix @kiranchandramohan ! p.s. please do feel free to assign me to anything like this if I miss it (and/or DM me on slack, as I tend to miss issues as they don't appear to get forwarded to my mail like PRs, not too sure what I need to subscribe to for that yet), but otherwise if you have the bandwidth and want to look into it of course go right ahead! Mainly just don't want to block issues being resolved in a timely manner :-)

[skatrak]

LGTM