[gcc(refs/vendors/ARM/heads/arm-struct-reorg-wip)] PR fortran/95500 - Segfault compiling extra interface on intrinsic

[Tamar Christina]

https://gcc.gnu.org/g:4b3ea558da6479dabe5841bcb0f6bad3f7fea858

commit 4b3ea558da6479dabe5841bcb0f6bad3f7fea858
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Thu Jun 4 21:00:33 2020 +0200

    PR fortran/95500 - Segfault compiling extra interface on intrinsic
    
    Converting an expression so that it can be passed by reference could
    result in a NULL pointer dereference.
    
    2020-06-04  Steven G. Kargl  <kargl@gcc.gnu.org>
                Harald Anlauf  <anlauf@gmx.de>
    
    gcc/fortran/
            PR fortran/95500
            * trans-expr.c (gfc_conv_expr_reference): Do not dereference NULL
            pointer.
    
    gcc/testsuite/
            PR fortran/95500
            * gfortran.dg/pr95500.f90: New test.
    
    (cherry picked from commit 8c727bdf4acf28c8315b119a1c8f6d6af745c2af)

Diff:
---
 gcc/fortran/trans-expr.c              |  1 +
 gcc/testsuite/gfortran.dg/pr95500.f90 | 15 +++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/gcc/fortran/trans-expr.c b/gcc/fortran/trans-expr.c
index 33fc061d89b..69147c4b81c 100644
--- a/gcc/fortran/trans-expr.c
+++ b/gcc/fortran/trans-expr.c
@@ -8810,6 +8810,7 @@ gfc_conv_expr_reference (gfc_se * se, gfc_expr * expr, bool add_clobber)
 
   if (expr->expr_type == EXPR_FUNCTION
       && ((expr->value.function.esym
+	   && expr->value.function.esym->result
 	   && expr->value.function.esym->result->attr.pointer
 	   && !expr->value.function.esym->result->attr.dimension)
 	  || (!expr->value.function.esym && !expr->ref
diff --git a/gcc/testsuite/gfortran.dg/pr95500.f90 b/gcc/testsuite/gfortran.dg/pr95500.f90
new file mode 100644
index 00000000000..e9eb7c65c86
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr95500.f90
@@ -0,0 +1,15 @@
+! { dg-do compile }
+! PR fortran/95500 - ICE compiling extra interface on intrinsic
+
+program test_intrinsic
+  implicit none
+  intrinsic :: alog
+  intrinsic :: dlog
+  real (4), parameter :: one = 1
+
+  interface ln
+     procedure :: alog, dlog
+  end interface ln
+
+  write (*,*) 'ln  1', ln (one)
+end program test_intrinsic