re PR libfortran/16080 (segmentation fault when reading empty string)

2004-06-19  Bud Davis  <bdavis9659@comcast.net>

      PR gfortran/16080
      * gfortran.fortran-torture/execute/read_null_string.f90: New file.
      * io/list_read.c(set_value): don't copy if the string is null.

From-SVN: r83388

gcc/testsuite/ChangeLog

+2004-06-19  Bud Davis  <bdavis9659@comcast.net>
+ 
+        PR gfortran/16080
+	* gfortran.fortran-torture/execute/read_null_string.f90: New file.
+
 2004-06-19  Andrew Pinski  <pinskia@physics.uc.edu>
 
 	* g++.dg/lookup/crash3.C: Use __SIZE_TYPE__

gcc/testsuite/gfortran.fortran-torture/execute/read_null_string.f90

+! pr 16080, segfault on reading an empty string 
+      implicit none 
+      integer t 
+      character*20   temp_name 
+      character*2 quotes
+      open(unit=7,status='SCRATCH')
+      quotes = '""""'  ! "" in the file
+      write(7,*)1
+      write(7,'(A)')quotes
+      temp_name = 'hello'  ! make sure the read overwrites it
+      rewind(7)
+      read(7, *) t 
+      read(7, *) temp_name 
+      if (temp_name.ne.'') call abort
+      end

libgfortran/ChangeLog

+2004-06-19  Bud Davis  <bdavis9659@comcast.net>
+
+	PR gfortran/16080
+	* io/list_read.c(set_value): don't copy if the string is null.
+
 2004-06-14  Bud Davis  <bdavis9659@comcast.net>
 
 	PR gfortran/15292

libgfortran/io/list_read.c

@@ -1313,8 +1313,13 @@ set_value:
       break;
 
     case BT_CHARACTER:
-      m = (len < saved_used) ? len : saved_used;
-      memcpy (p, saved_string, m);
+      if (saved_string)
+       { 
+          m = (len < saved_used) ? len : saved_used;
+          memcpy (p, saved_string, m);
+       }
+      else    /* just delimeters encountered, nothing to copy but SPACE */
+        m = 0;
 
       if (m < len)
 	memset (((char *) p) + m, ' ', len - m);