Fix private overwrite flag

find_def_in_most_recent_scope() set the private bit to 0 when it found an alias. This was most likely unintended and could cause issues when resolving multiple definitions of the same symbol at a later stage (if a private symbol appeared to be publicly available).

Tests for private flag overwrite added, based on flang github issue #890.

test/f90_correct/inc/use00.mk

@@ -0,0 +1,20 @@
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+
+########## Make rule for test use00  ########
+
+build:
+	@echo ------------------------------------ building test $(TEST)
+	-$(CC) -c $(CFLAGS) $(SRC)/check.c -o check.$(OBJX)
+	-$(FC) -c $(FFLAGS) $(LDFLAGS) $(SRC)/$(TEST).f90 -o $(TEST).$(OBJX)
+	-$(FC) $(FFLAGS) $(LDFLAGS) $(TEST).$(OBJX) check.$(OBJX) $(LIBS) -o $(TEST).$(EXESUFFIX)
+
+run:
+	@echo ------------------------------------ executing test $(TEST)
+	./$(TEST).$(EXESUFFIX)
+
+verify: ;
+

test/f90_correct/lit/use00.sh

@@ -0,0 +1,9 @@
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+# Shared lit script for each tests. Run bash commands that run tests with make.
+
+# RUN: KEEP_FILES=%keep FLAGS=%flags TEST_SRC=%s MAKE_FILE_DIR=%S/.. bash %S/runmake | tee %t 
+# RUN: cat %t | FileCheck %S/runmake

test/f90_correct/src/use00.f90

@@ -0,0 +1,39 @@
+module f_precisions
+  integer, parameter, public :: f_double = selected_real_kind(15, 307)
+end module f_precisions
+
+module box
+  use f_precisions, gp=>f_double
+  private
+  public :: get_gp
+contains
+  subroutine get_gp(out_val)
+    integer, intent(out) :: out_val
+    out_val = gp
+  end subroutine get_gp
+end module box
+
+module Poisson_Solver
+  use f_precisions
+  integer, parameter, public :: gp=f_double
+end module Poisson_Solver
+
+module module_defs
+  use f_precisions
+  integer, parameter, public :: gp=f_double
+end module module_defs
+
+subroutine PSolver(eh)
+  use module_defs ! This has a public gp
+  use box ! This has a private gp
+  use Poisson_Solver, except_gp => gp ! This has a public gp
+  real(gp), intent(out) :: eh ! Should be able to use gp from module_base
+end subroutine PSolver
+
+program main
+  use box
+  use Poisson_Solver
+  integer :: box_gp
+  call get_gp(box_gp)
+  call check(box_gp, gp, 1) ! box's gp and Solver's gp alias the same variable
+end program

tools/flang1/flang1exe/module.c

@@ -503,7 +503,6 @@ find_def_in_most_recent_scope(int sptr, int save_sem_scope_level)
     if (NMPTRG(sptr1) != NMPTRG(sptr))
       continue;
     if (STYPEG(sptr1) == ST_ALIAS && aliased_sym_visible(sptr1)) {
-      PRIVATEP(sptr1, 0);
       HIDDENP(SYMLKG(sptr1), 0);
     }
     if (STYPEG(sptr1) == ST_ALIAS) {