[Bug fortran/28081] New: Undue compile-time error for zero-sized substring

[Bug fortran/28081] New: Undue compile-time error for zero-sized substring

[fxcoudert at gcc dot gnu dot org]

The following error should not happen:

$ cat substr_3.f 
      implicit none
      character(len=10) :: s, t
      integer :: i, j

      s = "abcdefghij"
      t(:10) = s(1:)
      s(16:15) = "foo"
      if (s /= t) call abort
      end
$ gfortran substr_3.f
 In file substr_3.f:9

      s(16:15) = "foo"                                                  
       1
Error: Substring end index at (1) is out of bounds


-- 
           Summary: Undue compile-time error for zero-sized substring
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: fxcoudert at gcc dot gnu dot org
        ReportedBy: fxcoudert at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28081

[Bug fortran/28081] Undue compile-time error for zero-sized substring

[fxcoudert at gcc dot gnu dot org]

------- Comment #1 from fxcoudert at gcc dot gnu dot org  2006-06-19 11:39 -------
Here is a patch that fixes this problem (and gives a slightly better, IMHO,
error message):

Index: resolve.c
===================================================================
--- resolve.c   (revision 114721)
+++ resolve.c   (working copy)
@@ -2542,7 +2542,9 @@
          return FAILURE;
        }

-      if (compare_bound_int (ref->u.ss.start, 1) == CMP_LT)
+      if (compare_bound_int (ref->u.ss.start, 1) == CMP_LT
+         && (compare_bound (ref->u.ss.end, ref->u.ss.start) == CMP_EQ
+             || compare_bound (ref->u.ss.end, ref->u.ss.start) == CMP_GT))
        {
          gfc_error ("Substring start index at %L is less than one",
                     &ref->u.ss.start->where);
@@ -2570,9 +2572,11 @@
        }

       if (ref->u.ss.length != NULL
-         && compare_bound (ref->u.ss.end, ref->u.ss.length->length) == CMP_GT)
+         && compare_bound (ref->u.ss.end, ref->u.ss.length->length) == CMP_GT
+         && (compare_bound (ref->u.ss.end, ref->u.ss.start) == CMP_EQ
+             || compare_bound (ref->u.ss.end, ref->u.ss.start) == CMP_GT))
        {
-         gfc_error ("Substring end index at %L is out of bounds",
+         gfc_error ("Substring end index at %L exceeds the string length",
                     &ref->u.ss.start->where);
          return FAILURE;
        }


-- 

fxcoudert at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
           Keywords|                            |patch
      Known to fail|                            |4.2.0 4.1.2
   Last reconfirmed|0000-00-00 00:00:00         |2006-06-19 11:39:33
               date|                            |
   Target Milestone|---                         |4.1.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28081

[Bug fortran/28081] Undue compile-time error for zero-sized substring

[fxcoudert at gcc dot gnu dot org]

------- Comment #2 from fxcoudert at gcc dot gnu dot org  2006-06-24 18:10 -------
Subject: Bug 28081

Author: fxcoudert
Date: Sat Jun 24 18:10:47 2006
New Revision: 114972

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=114972
Log:
        PR fortran/28081

        * resolve.c (resolve_substring): Don't issue out-of-bounds
        error messages when the range has zero size.

        * gfortran.dg/substr_3.f: New test.
        * gfortran.dg/equiv_2.f90: Update expected error message.

Added:
    trunk/gcc/testsuite/gfortran.dg/substr_3.f
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/resolve.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gfortran.dg/equiv_2.f90


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28081

[Bug fortran/28081] [4.1 only] Undue compile-time error for zero-sized substring

[fxcoudert at gcc dot gnu dot org]

------- Comment #3 from fxcoudert at gcc dot gnu dot org  2006-07-02 21:17 -------
Subject: Bug 28081

Author: fxcoudert
Date: Sun Jul  2 21:17:05 2006
New Revision: 115134

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=115134
Log:
        PR fortran/28094
        * trans-intrinsic.c (gfc_conv_intrinsic_mod): Support cases where
        there is no integer kind equal to the resulting real kind.
        * intrinsic.c (add_functions): MODULO is not allowed as an actual
        argument.
        * Makefile.am: Add _mod_r10.F90 and _mod_r16.F90.
        * Makefile.in: Regenerate.
        * generated/_mod_r10.F90: New file.
        * generated/_mod_r16.F90: New file.

        PR fortran/27965
        * trans-array.c (gfc_conv_ss_startstride): Correct the runtime
        conditions for bounds-checking. Check for nonzero stride.
        Don't check the last dimension of assumed-size arrays. Fix the
        dimension displayed in the error message.

        PR fortran/26801
        * trans-intrinsic.c (gfc_conv_associated): Use pre and post blocks
        of the scalarization expression.
        * gfortran.dg/associated_4.f90: New test.

        PR fortran/28081
        * resolve.c (resolve_substring): Don't issue out-of-bounds
        error messages when the range has zero size.
        * gfortran.dg/substr_3.f: New test.
        * gfortran.dg/equiv_2.f90: Update expected error message.

        PR fortran/23862
        * lang-specs.h (f95-cpp-input): Pass -ffree-form to f951 unless
        -ffixed-form is explicitly specified.

Added:
    branches/gcc-4_1-branch/gcc/testsuite/gfortran.dg/associated_4.f90
      - copied unchanged from r114757,
trunk/gcc/testsuite/gfortran.dg/associated_4.f90
    branches/gcc-4_1-branch/gcc/testsuite/gfortran.dg/substr_3.f
      - copied unchanged from r114972,
trunk/gcc/testsuite/gfortran.dg/substr_3.f
    branches/gcc-4_1-branch/libgfortran/generated/_mod_r10.F90
      - copied unchanged from r114961, trunk/libgfortran/generated/_mod_r10.F90
    branches/gcc-4_1-branch/libgfortran/generated/_mod_r16.F90
      - copied unchanged from r114961, trunk/libgfortran/generated/_mod_r16.F90
Modified:
    branches/gcc-4_1-branch/gcc/fortran/ChangeLog
    branches/gcc-4_1-branch/gcc/fortran/intrinsic.c
    branches/gcc-4_1-branch/gcc/fortran/lang-specs.h
    branches/gcc-4_1-branch/gcc/fortran/resolve.c
    branches/gcc-4_1-branch/gcc/fortran/trans-array.c
    branches/gcc-4_1-branch/gcc/fortran/trans-intrinsic.c
    branches/gcc-4_1-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_1-branch/gcc/testsuite/gfortran.dg/equiv_2.f90
    branches/gcc-4_1-branch/libgfortran/ChangeLog
    branches/gcc-4_1-branch/libgfortran/Makefile.am
    branches/gcc-4_1-branch/libgfortran/Makefile.in


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28081

[Bug fortran/28081] Undue compile-time error for zero-sized substring

[fxcoudert at gcc dot gnu dot org]

------- Comment #4 from fxcoudert at gcc dot gnu dot org  2006-07-02 21:23 -------
Fixed.


-- 

fxcoudert at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
      Known to fail|4.1.2                       |
      Known to work|4.2.0                       |4.2.0 4.1.2
         Resolution|                            |FIXED
            Summary|[4.1 only] Undue compile-   |Undue compile-time error for
                   |time error for zero-sized   |zero-sized substring
                   |substring                   |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28081