From: Harald Anlauf <anlauf@gmx.de>
Date: Thu, 3 Dec 2020 19:33:22 +0000 (+0100)
Subject: PR fortran/95342 - ICE in gfc_match_subroutine, at fortran/decl.c:7913
X-Git-Tag: releases/gcc-10.3.0~542
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=316a185ee29c9e6ec060762e76d25b64c60fd665;p=thirdparty%2Fgcc.git

PR fortran/95342 - ICE in gfc_match_subroutine, at fortran/decl.c:7913

Add checks for NULL pointers before dereferencing them.

gcc/fortran/ChangeLog:

	PR fortran/95342
	* decl.c (gfc_match_function_decl): Avoid NULL pointer dereference.
	(gfc_match_subroutine): Likewise.

gcc/testsuite/ChangeLog:

	PR fortran/95342
	* gfortran.dg/pr95342.f90: New test.

(cherry picked from commit 30b606bb9b9314010a446ea4bed3481632008f75)
---

diff --git a/gcc/fortran/decl.c b/gcc/fortran/decl.c
index c1a15f1a84ae..9273976aa9a1 100644
--- a/gcc/fortran/decl.c
+++ b/gcc/fortran/decl.c
@@ -7390,6 +7390,7 @@ gfc_match_function_decl (void)
      procedure interface body.  */
     if (sym->attr.is_bind_c && sym->attr.module_procedure && sym->old_symbol
   	&& strcmp (sym->name, sym->old_symbol->name) == 0
+	&& sym->binding_label && sym->old_symbol->binding_label
 	&& strcmp (sym->binding_label, sym->old_symbol->binding_label) != 0)
       {
 	  const char *null = "NULL", *s1, *s2;
@@ -7905,6 +7906,7 @@ gfc_match_subroutine (void)
 	 procedure interface body.  */
       if (sym->attr.module_procedure && sym->old_symbol
   	  && strcmp (sym->name, sym->old_symbol->name) == 0
+	  && sym->binding_label && sym->old_symbol->binding_label
 	  && strcmp (sym->binding_label, sym->old_symbol->binding_label) != 0)
 	{
 	  const char *null = "NULL", *s1, *s2;
diff --git a/gcc/testsuite/gfortran.dg/pr95342.f90 b/gcc/testsuite/gfortran.dg/pr95342.f90
new file mode 100644
index 000000000000..41c987d3bbbe
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr95342.f90
@@ -0,0 +1,20 @@
+! { dg-do compile }
+! PR fortran/95342 - ICE in gfc_match_subroutine, at fortran/decl.c:7913
+
+module m1
+  interface
+     module subroutine s()
+     end
+     subroutine s() bind(c) ! { dg-error "EXTERNAL attribute conflicts" }
+     end                    ! { dg-error "END INTERFACE" }
+  end interface
+end
+
+module m2
+  interface
+     module function f()
+     end
+     function f() bind(c)
+     end                    ! { dg-error "Duplicate EXTERNAL attribute" }
+  end interface
+end