[gcc r13-6592] Fortran: fix ICE with bind(c) in block data [PR104332]

[Harald Anlauf <anlauf@gcc.gnu.org>]

https://gcc.gnu.org/g:e20e5d9dc11b64e8eabce6803c91cb5768207083

commit r13-6592-ge20e5d9dc11b64e8eabce6803c91cb5768207083
Author: Harald Anlauf <anlauf@gmx.de>
Date:   Thu Mar 9 18:59:08 2023 +0100

    Fortran: fix ICE with bind(c) in block data [PR104332]
    
    gcc/fortran/ChangeLog:
    
            PR fortran/104332
            * resolve.cc (resolve_symbol): Avoid NULL pointer dereference while
            checking a symbol with the BIND(C) attribute.
    
    gcc/testsuite/ChangeLog:
    
            PR fortran/104332
            * gfortran.dg/bind_c_usage_34.f90: New test.

Diff:
---
 gcc/fortran/resolve.cc                        |  4 ++--
 gcc/testsuite/gfortran.dg/bind_c_usage_34.f90 | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/gcc/fortran/resolve.cc b/gcc/fortran/resolve.cc
index 2780c82c798..46585879ddc 100644
--- a/gcc/fortran/resolve.cc
+++ b/gcc/fortran/resolve.cc
@@ -15933,8 +15933,8 @@ resolve_symbol (gfc_symbol *sym)
 
       /* First, make sure the variable is declared at the
 	 module-level scope (J3/04-007, Section 15.3).	*/
-      if (sym->ns->proc_name->attr.flavor != FL_MODULE &&
-          sym->attr.in_common == 0)
+      if (!(sym->ns->proc_name && sym->ns->proc_name->attr.flavor == FL_MODULE)
+	  && !sym->attr.in_common)
 	{
 	  gfc_error ("Variable %qs at %L cannot be BIND(C) because it "
 		     "is neither a COMMON block nor declared at the "
diff --git a/gcc/testsuite/gfortran.dg/bind_c_usage_34.f90 b/gcc/testsuite/gfortran.dg/bind_c_usage_34.f90
new file mode 100644
index 00000000000..40c8e9363cf
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/bind_c_usage_34.f90
@@ -0,0 +1,21 @@
+! { dg-do compile }
+! PR fortran/104332 - ICE with bind(c) in block data
+! Contributed by G. Steinmetz
+
+block data
+  bind(c) :: a ! { dg-error "cannot be BIND\\(C\\)" }
+end
+
+block data aa
+   real, bind(c) :: a ! { dg-error "cannot be BIND\\(C\\)" }
+end
+
+block data bb
+   real    :: a ! { dg-error "cannot be BIND\\(C\\)" }
+   bind(c) :: a
+end
+
+block data cc
+   common /a/ x
+   bind(c) :: /a/
+end