[flang] Give internal linkage to internal procedures (#81929)

Internal procedures cannot be called directly from outside the host procedure, so there is no point giving them external linkage. The only reason flang did is because it is the default in MLIR. Giving external linkage to them: - prevents deleting them when not used/inlined by LLVM - causes bugs with shared libraries (at least on linux x86-64) because the call to the internal function could lead to a dynamic loader call that would overwrite r10 register (the static chain pointer) due to system calls and did not restore (it seems it does not expect r10 to be used for PLT calls). This patch gives internal linkage to internal procedures: Note: the llvm.linkage attribute name cannot be obtained via a getLinkageAttrName since it is not the same name as the one used in the LLVM dialect. It is just a placeholder defined in mlir/lib/Conversion/FuncToLLVM/FuncToLLVM.cpp until the func dialect gets a real linkage model. So simply avoid hard coding it too many times in lowering.
llvm · Feb 28, 2024 · 06f775a · 06f775a
1 parent 915fce0
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diff --git a/flang/include/flang/Optimizer/Builder/FIRBuilder.h b/flang/include/flang/Optimizer/Builder/FIRBuilder.h
@@ -688,6 +688,9 @@ fir::BoxValue createBoxValue(fir::FirOpBuilder &builder, mlir::Location loc,
 /// Generate Null BoxProc for procedure pointer null initialization.
 mlir::Value createNullBoxProc(fir::FirOpBuilder &builder, mlir::Location loc,
                               mlir::Type boxType);
+
+/// Set internal linkage attribute on a function.
+void setInternalLinkage(mlir::func::FuncOp);
 } // namespace fir::factory
 
 #endif // FORTRAN_OPTIMIZER_BUILDER_FIRBUILDER_H
diff --git a/flang/lib/Lower/Bridge.cpp b/flang/lib/Lower/Bridge.cpp
@@ -4488,7 +4488,16 @@ class FirConverter : public Fortran::lower::AbstractConverter {
     assert(builder && "FirOpBuilder did not instantiate");
     builder->setFastMathFlags(bridge.getLoweringOptions().getMathOptions());
     builder->setInsertionPointToStart(&func.front());
-    func.setVisibility(mlir::SymbolTable::Visibility::Public);
+    if (funit.parent.isA<Fortran::lower::pft::FunctionLikeUnit>()) {
+      // Give internal linkage to internal functions. There are no name clash
+      // risks, but giving global linkage to internal procedure will break the
+      // static link register in shared libraries because of the system calls.
+      // Also, it should be possible to eliminate the procedure code if all the
+      // uses have been inlined.
+      fir::factory::setInternalLinkage(func);
+    } else {
+      func.setVisibility(mlir::SymbolTable::Visibility::Public);
+    }
     assert(blockId == 0 && "invalid blockId");
     assert(activeConstructStack.empty() && "invalid construct stack state");
 

diff --git a/flang/lib/Optimizer/Builder/FIRBuilder.cpp b/flang/lib/Optimizer/Builder/FIRBuilder.cpp
@@ -18,6 +18,7 @@
 #include "flang/Optimizer/Dialect/FIROpsSupport.h"
 #include "flang/Optimizer/Support/FatalError.h"
 #include "flang/Optimizer/Support/InternalNames.h"
+#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
 #include "mlir/Dialect/OpenACC/OpenACC.h"
 #include "mlir/Dialect/OpenMP/OpenMPDialect.h"
 #include "llvm/ADT/ArrayRef.h"
@@ -1533,3 +1534,10 @@ mlir::Value fir::factory::createNullBoxProc(fir::FirOpBuilder &builder,
   mlir::Value initVal{builder.create<fir::ZeroOp>(loc, boxEleTy)};
   return builder.create<fir::EmboxProcOp>(loc, boxTy, initVal);
 }
+
+void fir::factory::setInternalLinkage(mlir::func::FuncOp func) {
+  auto internalLinkage = mlir::LLVM::linkage::Linkage::Internal;
+  auto linkage =
+      mlir::LLVM::LinkageAttr::get(func->getContext(), internalLinkage);
+  func->setAttr("llvm.linkage", linkage);
+}
diff --git a/flang/lib/Optimizer/Builder/IntrinsicCall.cpp b/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
@@ -1834,10 +1834,7 @@ mlir::func::FuncOp IntrinsicLibrary::getWrapper(GeneratorType generator,
     // First time this wrapper is needed, build it.
     function = builder.createFunction(loc, wrapperName, funcType);
     function->setAttr("fir.intrinsic", builder.getUnitAttr());
-    auto internalLinkage = mlir::LLVM::linkage::Linkage::Internal;
-    auto linkage =
-        mlir::LLVM::LinkageAttr::get(builder.getContext(), internalLinkage);
-    function->setAttr("llvm.linkage", linkage);
+    fir::factory::setInternalLinkage(function);
     function.addEntryBlock();
 
     // Create local context to emit code into the newly created function

diff --git a/flang/test/Lower/HLFIR/allocatable-end-of-scope-dealloc.f90 b/flang/test/Lower/HLFIR/allocatable-end-of-scope-dealloc.f90
@@ -224,7 +224,7 @@ subroutine internal()
     allocate(x)
   end subroutine
 end subroutine
-! CHECK-LABEL:   func.func @_QFno_dealloc_host_assocPinternal
+! CHECK-LABEL:   func.func private @_QFno_dealloc_host_assocPinternal
 ! CHECK-NOT: freemem
 ! CHECK-NOT: Deallocate
 ! CHECK: return

diff --git a/flang/test/Lower/HLFIR/bindc_internal_proc.f90 b/flang/test/Lower/HLFIR/bindc_internal_proc.f90
@@ -3,7 +3,7 @@
 ! internal procedures.
 ! RUN: bbc -emit-hlfir %s -o - | FileCheck %s
 
-!CHECK: func.func @_QFsub1Pfoo(%{{.*}}: i32
+!CHECK: func.func private @_QFsub1Pfoo(%{{.*}}: i32
 subroutine sub1()
   call foo(42)
 contains
@@ -13,7 +13,7 @@ subroutine foo(i) bind(c)
   end subroutine
 end subroutine
 
-!CHECK: func.func @_QFsub2Pfoo(%{{.*}}: i64
+!CHECK: func.func private @_QFsub2Pfoo(%{{.*}}: i64
 subroutine sub2()
   call foo(42_8)
 contains

diff --git a/flang/test/Lower/HLFIR/internal-procedures-2.f90 b/flang/test/Lower/HLFIR/internal-procedures-2.f90
@@ -23,7 +23,7 @@ subroutine internal_procedure(i, mask)
   end forall
  end subroutine
 end subroutine
-! CHECK-LABEL: func.func @_QFhost_procedurePinternal_procedure(
+! CHECK-LABEL: func.func private @_QFhost_procedurePinternal_procedure(
 ! CHECK:    fir.address_of(@_QMmodule_used_by_hostEindexed_by_var) : !fir.ref<!fir.array<2xi32>>
 ! CHECK:    fir.address_of(@_QMmodule_used_by_hostEref_in_forall) : !fir.ref<!fir.array<2xi32>>
 ! CHECK:    fir.address_of(@_QMmodule_used_by_hostEref_in_implied_do) : !fir.ref<i32>
diff --git a/flang/test/Lower/HLFIR/internal-procedures.f90 b/flang/test/Lower/HLFIR/internal-procedures.f90
@@ -9,8 +9,8 @@ subroutine internal
   call takes_array(x)
 end subroutine
 end subroutine
-! CHECK-LABEL: func.func @_QFtest_explicit_shape_arrayPinternal(
-! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<tuple<!fir.box<!fir.array<?xf32>>>> {fir.host_assoc}) attributes {fir.internal_proc} {
+! CHECK-LABEL: func.func private @_QFtest_explicit_shape_arrayPinternal(
+! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<tuple<!fir.box<!fir.array<?xf32>>>> {fir.host_assoc}) attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! CHECK:  %[[VAL_1:.*]] = arith.constant 0 : i32
 ! CHECK:  %[[VAL_2:.*]] = fir.coordinate_of %[[VAL_0]], %[[VAL_1]] : (!fir.ref<tuple<!fir.box<!fir.array<?xf32>>>>, i32) -> !fir.ref<!fir.box<!fir.array<?xf32>>>
 ! CHECK:  %[[VAL_3:.*]] = fir.load %[[VAL_2]] : !fir.ref<!fir.box<!fir.array<?xf32>>>
@@ -27,8 +27,8 @@ subroutine internal
   call takes_array(x)
 end subroutine
 end subroutine
-! CHECK-LABEL: func.func @_QFtest_assumed_shapePinternal(
-! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<tuple<!fir.box<!fir.array<?xf32>>>> {fir.host_assoc}) attributes {fir.internal_proc} {
+! CHECK-LABEL: func.func private @_QFtest_assumed_shapePinternal(
+! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<tuple<!fir.box<!fir.array<?xf32>>>> {fir.host_assoc}) attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! CHECK:  %[[VAL_1:.*]] = arith.constant 0 : i32
 ! CHECK:  %[[VAL_2:.*]] = fir.coordinate_of %[[VAL_0]], %[[VAL_1]] : (!fir.ref<tuple<!fir.box<!fir.array<?xf32>>>>, i32) -> !fir.ref<!fir.box<!fir.array<?xf32>>>
 ! CHECK:  %[[VAL_3:.*]] = fir.load %[[VAL_2]] : !fir.ref<!fir.box<!fir.array<?xf32>>>
@@ -44,8 +44,8 @@ subroutine internal()
   call bar(c)
 end subroutine
 end subroutine
-! CHECK-LABEL:   func.func @_QFtest_scalar_charPinternal(
-! CHECK-SAME:                               %[[VAL_0:.*]]: !fir.ref<tuple<!fir.boxchar<1>>> {fir.host_assoc}) attributes {fir.internal_proc} {
+! CHECK-LABEL:   func.func private @_QFtest_scalar_charPinternal(
+! CHECK-SAME:                               %[[VAL_0:.*]]: !fir.ref<tuple<!fir.boxchar<1>>> {fir.host_assoc}) attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! CHECK:  %[[VAL_1:.*]] = arith.constant 0 : i32
 ! CHECK:  %[[VAL_2:.*]] = fir.coordinate_of %[[VAL_0]], %[[VAL_1]] : (!fir.ref<tuple<!fir.boxchar<1>>>, i32) -> !fir.ref<!fir.boxchar<1>>
 ! CHECK:  %[[VAL_3:.*]] = fir.load %[[VAL_2]] : !fir.ref<!fir.boxchar<1>>

diff --git a/flang/test/Lower/Intrinsics/random.f90 b/flang/test/Lower/Intrinsics/random.f90
@@ -45,7 +45,7 @@ subroutine random_test_2
   call foo(size)
   call bar(size, get)
 contains
-  ! CHECK-LABEL: func @_QFrandom_test_2Pfoo
+  ! CHECK-LABEL: func private @_QFrandom_test_2Pfoo
   subroutine foo(size, put, get)
     ! CHECK: [[s1:%[0-9]+]] = fir.is_present %arg0
     ! CHECK: [[s2:%[0-9]+]] = fir.embox %arg0
@@ -70,7 +70,7 @@ subroutine foo(size, put, get)
     print*, size
   end subroutine
 
-  ! CHECK-LABEL: func @_QFrandom_test_2Pbar
+  ! CHECK-LABEL: func private @_QFrandom_test_2Pbar
   subroutine bar(size, get, put)
     integer, optional :: size
     ! CHECK: [[p1:%[0-9]+]] = fir.is_present %arg2

diff --git a/flang/test/Lower/Intrinsics/ubound01.f90 b/flang/test/Lower/Intrinsics/ubound01.f90
@@ -16,7 +16,7 @@ subroutine s2(a,n,n2)
   End Subroutine
 end
 
-! CHECK-LABEL: func.func @_QFPs2
+! CHECK-LABEL: func.func private @_QFPs2
 ! CHECK-SAME: %[[ARG0:.*]]: !fir.box<!fir.array<?x?xf32>>
 ! CHECK: %[[BOX:.*]] = fir.rebox %[[ARG0]](%{{.*}}) : (!fir.box<!fir.array<?x?xf32>>, !fir.shift<2>) -> !fir.box<!fir.array<?x?xf32>>
 ! CHECK: %[[BOX_NONE:.*]] = fir.convert %[[BOX]] : (!fir.box<!fir.array<?x?xf32>>) -> !fir.box<none>

diff --git a/flang/test/Lower/OpenACC/acc-routine04.f90 b/flang/test/Lower/OpenACC/acc-routine04.f90
@@ -31,4 +31,4 @@ subroutine sub2()
 ! CHECK: acc.routine @acc_routine_0 func(@_QMdummy_modPsub1) seq
 ! CHECK: func.func @_QMdummy_modPsub1(%arg0: !fir.ref<i32> {fir.bindc_name = "i"}) attributes {acc.routine_info = #acc.routine_info<[@acc_routine_0]>}
 ! CHECK: func.func @_QQmain() attributes {fir.bindc_name = "test_acc_routine"}
-! CHECK: func.func @_QFPsub2() attributes {acc.routine_info = #acc.routine_info<[@acc_routine_1]>}
+! CHECK: func.func private @_QFPsub2() attributes {acc.routine_info = #acc.routine_info<[@acc_routine_1]>, llvm.linkage = #llvm.linkage<internal>}
diff --git a/flang/test/Lower/OpenMP/FIR/threadprivate-use-association-2.f90 b/flang/test/Lower/OpenMP/FIR/threadprivate-use-association-2.f90
@@ -17,7 +17,7 @@ module m
 ! CHECK:         return
 ! CHECK:       }
 !
-! CHECK-LABEL: func.func @_QMm2FtestPinternal_test() {
+! CHECK-LABEL: func.func private @_QMm2FtestPinternal_test() {{.*}} {
 ! CHECK:         %[[VAL_0:.*]] = fir.address_of(@_QMmEx) : !fir.ref<i32>
 ! CHECK:         %[[VAL_1:.*]] = omp.threadprivate %[[VAL_0]] : !fir.ref<i32> -> !fir.ref<i32>
 ! CHECK:         fir.call @_QPbar(%[[VAL_1]]) {{.*}}: (!fir.ref<i32>) -> ()

diff --git a/flang/test/Lower/OpenMP/threadprivate-commonblock-use.f90 b/flang/test/Lower/OpenMP/threadprivate-commonblock-use.f90
@@ -15,7 +15,7 @@ module  m1
   subroutine ss1
     use m0
   contains
-!CHECK-LABEL: func @_QMm1Fss1Pss2
+!CHECK-LABEL: func private @_QMm1Fss1Pss2
 !CHECK: %[[CMN:.*]] = fir.address_of(@cmn_) : !fir.ref<!fir.array<4xi8>>
 !CHECK: omp.parallel
 !CHECK: %{{.*}} = omp.threadprivate %[[CMN]] : !fir.ref<!fir.array<4xi8>> -> !fir.ref<!fir.array<4xi8>>

diff --git a/flang/test/Lower/OpenMP/threadprivate-use-association-2-hlfir.f90 b/flang/test/Lower/OpenMP/threadprivate-use-association-2-hlfir.f90
@@ -19,7 +19,7 @@ module m
 ! CHECK:         return
 ! CHECK:       }
 
-! CHECK-LABEL: func.func @_QMm2FtestPinternal_test() {
+! CHECK-LABEL: func.func private @_QMm2FtestPinternal_test() {{.*}} {
 ! CHECK:         %[[VAL_0:.*]] = fir.address_of(@_QMmEx) : !fir.ref<i32>
 ! CHECK:         %[[VAL_1:.*]]:2 = hlfir.declare %[[VAL_0]] {uniq_name = "_QMmEx"} : (!fir.ref<i32>) -> (!fir.ref<i32>, !fir.ref<i32>)
 ! CHECK:         %[[VAL_2:.*]] = omp.threadprivate %[[VAL_1]]#1 : !fir.ref<i32> -> !fir.ref<i32>

diff --git a/flang/test/Lower/PowerPC/ppc-vector-types.f90 b/flang/test/Lower/PowerPC/ppc-vector-types.f90
@@ -44,7 +44,7 @@ program ppc_vec_unit
       ! CHECK-LLVM-NEXT: store <512 x i1> %[[RESQ]], ptr @_QFEvq2, align 64
 
       contains
-      ! CHECK-LLVM-LABEL: define <4 x i32> @_QFPtest_vec_integer_assign
+      ! CHECK-LLVM-LABEL: define internal <4 x i32> @_QFPtest_vec_integer_assign
       function test_vec_integer_assign(arg1)
         ! CHECK-LLVM: %[[FUNC_RES:.*]] = alloca <4 x i32>, i64 1, align 16
         vector(integer(4)) :: arg1, test_vec_integer_assign
@@ -58,7 +58,7 @@ function test_vec_integer_assign(arg1)
         ! CHECK-LLVM-NEXT: ret <4 x i32> %[[RET]]
       end function test_vec_integer_assign
 
-      ! CHECK-LLVM-LABEL: define <2 x double> @_QFPtest_vec_real_assign
+      ! CHECK-LLVM-LABEL: define internal <2 x double> @_QFPtest_vec_real_assign
       function test_vec_real_assign(arg1)
         ! CHECK-LLVM: %[[FUNC_RES:.*]] = alloca <2 x double>, i64 1, align 16
         vector(real(8)) :: arg1, test_vec_real_assign
@@ -72,7 +72,7 @@ function test_vec_real_assign(arg1)
         ! CHECK-LLVM-NEXT: ret <2 x double> %[[RET]]
       end function test_vec_real_assign
 
-      ! CHECK-LLVM-LABEL: define <8 x i16> @_QFPtest_vec_unsigned_assign
+      ! CHECK-LLVM-LABEL: define internal <8 x i16> @_QFPtest_vec_unsigned_assign
       function test_vec_unsigned_assign(arg1)
         ! CHECK-LLVM: %[[FUNC_RES:.*]] = alloca <8 x i16>, i64 1, align 16
         vector(unsigned(2)) :: arg1, test_vec_unsigned_assign
@@ -86,7 +86,7 @@ function test_vec_unsigned_assign(arg1)
         ! CHECK-LLVM-NEXT: ret <8 x i16> %[[RET]]
       end function test_vec_unsigned_assign
 
-      ! CHECK-LLVM-LABEL: define <256 x i1> @_QFPtest_vec_pair_assign
+      ! CHECK-LLVM-LABEL: define internal <256 x i1> @_QFPtest_vec_pair_assign
       function test_vec_pair_assign(arg1)
         ! CHECK-LLVM: %[[FUNC_RES:.*]] = alloca <256 x i1>, i64 1, align 32
         __vector_pair :: arg1, test_vec_pair_assign
@@ -100,7 +100,7 @@ function test_vec_pair_assign(arg1)
         ! CHECK-LLVM-NEXT: ret <256 x i1> %[[RET]]
       end function test_vec_pair_assign
 
-      ! CHECK-LLVM-LABEL: define <512 x i1> @_QFPtest_vec_quad_assign
+      ! CHECK-LLVM-LABEL: define internal <512 x i1> @_QFPtest_vec_quad_assign
       function test_vec_quad_assign(arg1)
         ! CHECK-LLVM: %[[FUNC_RES:.*]] = alloca <512 x i1>, i64 1, align 64
         __vector_quad :: arg1, test_vec_quad_assign

diff --git a/flang/test/Lower/array-temp.f90 b/flang/test/Lower/array-temp.f90
@@ -404,7 +404,7 @@ subroutine tt1
   ! CHECK-NEXT: fir.call @_FortranAioEndIoStatement
   print*, [(r([7.0]),i=1,3)]
 contains
-  ! CHECK-LABEL: func @_QFtt1Pr
+  ! CHECK-LABEL: func private @_QFtt1Pr
   function r(x)
     real x(:)
     r = x(1)

diff --git a/flang/test/Lower/dummy-arguments.f90 b/flang/test/Lower/dummy-arguments.f90
@@ -9,7 +9,7 @@ program test1
   call foo(10)
 contains
 
-! CHECK-LABEL: func @_QFPfoo
+! CHECK-LABEL: func private @_QFPfoo
 subroutine foo(avar1)
   integer :: avar1
 !  integer :: my_data, my_data2

diff --git a/flang/test/Lower/dummy-procedure-character.f90 b/flang/test/Lower/dummy-procedure-character.f90
@@ -213,7 +213,7 @@ subroutine host(f)
   ! CHECK: fir.call @_QFhostPintern(%[[VAL_1]])
   call intern()
 contains
-! CHECK-LABEL: func @_QFhostPintern(
+! CHECK-LABEL: func private @_QFhostPintern(
 ! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<tuple<tuple<!fir.boxproc<() -> ()>, i64>>> {fir.host_assoc})
   subroutine intern()
 ! CHECK:  %[[VAL_1:.*]] = arith.constant 0 : i32
@@ -242,7 +242,7 @@ subroutine host2(f)
   ! CHECK: fir.call @_QFhost2Pintern(%[[VAL_1]])
   call intern()
 contains
-! CHECK-LABEL: func @_QFhost2Pintern(
+! CHECK-LABEL: func private @_QFhost2Pintern(
 ! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<tuple<tuple<!fir.boxproc<() -> ()>, i64>>> {fir.host_assoc})
   subroutine intern()
     ! CHECK:  %[[VAL_1:.*]] = fir.alloca !fir.char<1,42> {bindc_name = ".result"}

diff --git a/flang/test/Lower/equivalence-with-host-assoc.f90 b/flang/test/Lower/equivalence-with-host-assoc.f90
@@ -10,7 +10,7 @@ subroutine inner
     i1 = j1
   end subroutine inner
 end subroutine test1
-! FIR-LABEL:   func.func @_QFtest1Pinner() attributes {fir.internal_proc} {
+! FIR-LABEL:   func.func private @_QFtest1Pinner() attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! FIR:           %[[VAL_0:.*]] = fir.address_of(@_QFtest1Ei1) : !fir.ref<!fir.array<1xi32>>
 ! FIR:           %[[VAL_1:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<!fir.array<1xi32>>) -> !fir.ref<!fir.array<4xi8>>
 ! FIR:           %[[VAL_2:.*]] = arith.constant 0 : index
@@ -24,7 +24,7 @@ end subroutine test1
 ! FIR:           return
 ! FIR:         }
 
-! HLFIR-LABEL:   func.func @_QFtest1Pinner() attributes {fir.internal_proc} {
+! HLFIR-LABEL:   func.func private @_QFtest1Pinner() attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! HLFIR:           %[[VAL_0:.*]] = fir.address_of(@_QFtest1Ei1) : !fir.ref<!fir.array<1xi32>>
 ! HLFIR:           %[[VAL_1:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<!fir.array<1xi32>>) -> !fir.ref<!fir.array<4xi8>>
 ! HLFIR:           %[[VAL_2:.*]] = arith.constant 0 : index
@@ -54,7 +54,7 @@ subroutine inner
     end subroutine inner
   end subroutine host
 end module test2
-! FIR-LABEL:   func.func @_QMtest2FhostPinner() attributes {fir.internal_proc} {
+! FIR-LABEL:   func.func private @_QMtest2FhostPinner() attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! FIR:           %[[VAL_0:.*]] = fir.address_of(@_QMtest2FhostEf1) : !fir.ref<!fir.array<1xi32>>
 ! FIR:           %[[VAL_1:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<!fir.array<1xi32>>) -> !fir.ref<!fir.array<4xi8>>
 ! FIR:           %[[VAL_2:.*]] = arith.constant 0 : index
@@ -68,7 +68,7 @@ end module test2
 ! FIR:           return
 ! FIR:         }
 
-! HLFIR-LABEL:   func.func @_QMtest2FhostPinner() attributes {fir.internal_proc} {
+! HLFIR-LABEL:   func.func private @_QMtest2FhostPinner() attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! HLFIR:           %[[VAL_0:.*]] = fir.address_of(@_QMtest2FhostEf1) : !fir.ref<!fir.array<1xi32>>
 ! HLFIR:           %[[VAL_1:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<!fir.array<1xi32>>) -> !fir.ref<!fir.array<4xi8>>
 ! HLFIR:           %[[VAL_2:.*]] = arith.constant 0 : index
@@ -94,7 +94,7 @@ subroutine inner
     i1 = j1 + k1
   end subroutine inner
 end subroutine test3
-! FIR-LABEL:   func.func @_QFtest3Pinner() attributes {fir.internal_proc} {
+! FIR-LABEL:   func.func private @_QFtest3Pinner() attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! FIR:           %[[VAL_0:.*]] = fir.address_of(@blk_) : !fir.ref<tuple<i32>>
 ! FIR:           %[[VAL_1:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<tuple<i32>>) -> !fir.ref<!fir.array<?xi8>>
 ! FIR:           %[[VAL_2:.*]] = arith.constant 0 : index
@@ -115,7 +115,7 @@ end subroutine test3
 ! FIR:           return
 ! FIR:         }
 
-! HLFIR-LABEL:   func.func @_QFtest3Pinner() attributes {fir.internal_proc} {
+! HLFIR-LABEL:   func.func private @_QFtest3Pinner() attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! HLFIR:           %[[VAL_0:.*]] = fir.address_of(@blk_) : !fir.ref<tuple<i32>>
 ! HLFIR:           %[[VAL_1:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<tuple<i32>>) -> !fir.ref<!fir.array<?xi8>>
 ! HLFIR:           %[[VAL_2:.*]] = arith.constant 0 : index
@@ -149,7 +149,7 @@ subroutine inner
     i1 = j1 + k1
   end subroutine inner
 end subroutine test4
-! FIR-LABEL:   func.func @_QFtest4Pinner() attributes {fir.internal_proc} {
+! FIR-LABEL:   func.func private @_QFtest4Pinner() attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! FIR:           %[[VAL_0:.*]] = fir.address_of(@blk_) : !fir.ref<tuple<i32>>
 ! FIR:           %[[VAL_1:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<tuple<i32>>) -> !fir.ref<!fir.array<?xi8>>
 ! FIR:           %[[VAL_2:.*]] = arith.constant 0 : index
@@ -170,7 +170,7 @@ end subroutine test4
 ! FIR:           return
 ! FIR:         }
 
-! HLFIR-LABEL:   func.func @_QFtest4Pinner() attributes {fir.internal_proc} {
+! HLFIR-LABEL:   func.func private @_QFtest4Pinner() attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
 ! HLFIR:           %[[VAL_0:.*]] = fir.address_of(@blk_) : !fir.ref<tuple<i32>>
 ! HLFIR:           %[[VAL_1:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<tuple<i32>>) -> !fir.ref<!fir.array<?xi8>>
 ! HLFIR:           %[[VAL_2:.*]] = arith.constant 0 : index

diff --git a/flang/test/Lower/explicit-interface-results-2.f90 b/flang/test/Lower/explicit-interface-results-2.f90
@@ -69,8 +69,8 @@ subroutine host4()
   integer :: n
   call internal_proc_a()
 contains
-! CHECK-LABEL: func @_QFhost4Pinternal_proc_a
-! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<tuple<!fir.ref<i32>>> {fir.host_assoc}) attributes {fir.internal_proc} {
+! CHECK-LABEL: func private @_QFhost4Pinternal_proc_a
+! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<tuple<!fir.ref<i32>>> {fir.host_assoc}) attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
   subroutine internal_proc_a()
     call takes_array(return_array())
 ! CHECK:  %[[VAL_1:.*]] = arith.constant 0 : i32
@@ -94,7 +94,7 @@ subroutine host5()
   implicit none
   call internal_proc_a()
 contains
-! CHECK-LABEL: func @_QFhost5Pinternal_proc_a() attributes {fir.internal_proc} {
+! CHECK-LABEL: func private @_QFhost5Pinternal_proc_a() attributes {fir.internal_proc, llvm.linkage = #llvm.linkage<internal>} {
   subroutine internal_proc_a()
     call takes_array(return_array())
 ! CHECK:  %[[VAL_0:.*]] = fir.address_of(@_QMsome_moduleEn_module) : !fir.ref<i32>
@@ -115,7 +115,7 @@ subroutine host6()
   implicit none
   call internal_proc_a()
 contains
-! CHECK-LABEL: func @_QFhost6Pinternal_proc_a
+! CHECK-LABEL: func private @_QFhost6Pinternal_proc_a
   subroutine internal_proc_a()
     call takes_array(return_array())
 ! CHECK:  %[[VAL_0:.*]] = fir.address_of(@_QMsome_moduleEn_module) : !fir.ref<i32>
@@ -187,7 +187,7 @@ subroutine host9()
   common /mycom/ n_common
   call internal_proc_a()
 contains
-! CHECK-LABEL: func @_QFhost9Pinternal_proc_a
+! CHECK-LABEL: func private @_QFhost9Pinternal_proc_a
   subroutine internal_proc_a()
 ! CHECK:  %[[VAL_0:.*]] = arith.constant 0 : index
 ! CHECK:  %[[VAL_1:.*]] = fir.address_of(@mycom_) : !fir.ref<!fir.array<4xi8>>
@@ -213,7 +213,7 @@ subroutine host10()
   implicit none
   call internal_proc_a()
 contains
-! CHECK-LABEL: func @_QFhost10Pinternal_proc_a
+! CHECK-LABEL: func private @_QFhost10Pinternal_proc_a
   subroutine internal_proc_a()
     call takes_array(return_array())
 ! CHECK:  %[[VAL_0:.*]] = arith.constant 0 : index