[Bug fortran/85130] Substrings out of range are not rejected

[anlauf at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

anlauf at gcc dot gnu.org changed:

   What|Removed |Added

   Target Milestone|--- |9.5
 Resolution|--- |FIXED
 Status|ASSIGNED|RESOLVED

--- Comment #11 from anlauf at gcc dot gnu.org ---
Fixed on all open branches.  Closing.

[Bug fortran/85130] Substrings out of range are not rejected

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

--- Comment #10 from CVS Commits  ---
The releases/gcc-9 branch has been updated by Harald Anlauf
:

https://gcc.gnu.org/g:0fabf86a52c46db19026a956cf386da46fa4d0be

commit r9-9738-g0fabf86a52c46db19026a956cf386da46fa4d0be
Author: Harald Anlauf 
Date:   Mon Sep 13 19:26:35 2021 +0200

Fortran - fix handling of substring start and end indices

gcc/fortran/ChangeLog:

PR fortran/85130
* expr.c (find_substring_ref): Handle given substring start and
end indices as signed integers, not unsigned.

gcc/testsuite/ChangeLog:

PR fortran/85130
* gfortran.dg/substr_6.f90: Revert commit r8-7574, adding again
test that was erroneously considered as illegal.

(cherry picked from commit 8d93ba93d3b13ac3d3c34404cad87732c809605b)

[Bug fortran/85130] Substrings out of range are not rejected

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

--- Comment #9 from CVS Commits  ---
The releases/gcc-10 branch has been updated by Harald Anlauf
:

https://gcc.gnu.org/g:a1591a283767168982ff60414ee01aaa1400fbf8

commit r10-10142-ga1591a283767168982ff60414ee01aaa1400fbf8
Author: Harald Anlauf 
Date:   Mon Sep 13 19:26:35 2021 +0200

Fortran - fix handling of substring start and end indices

gcc/fortran/ChangeLog:

PR fortran/85130
* expr.c (find_substring_ref): Handle given substring start and
end indices as signed integers, not unsigned.

gcc/testsuite/ChangeLog:

PR fortran/85130
* gfortran.dg/substr_6.f90: Revert commit r8-7574, adding again
test that was erroneously considered as illegal.

(cherry picked from commit 8d93ba93d3b13ac3d3c34404cad87732c809605b)

[Bug fortran/85130] Substrings out of range are not rejected

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

--- Comment #8 from CVS Commits  ---
The releases/gcc-11 branch has been updated by Harald Anlauf
:

https://gcc.gnu.org/g:3bc4ed085145e1cb6089841c811094633eea7431

commit r11-9009-g3bc4ed085145e1cb6089841c811094633eea7431
Author: Harald Anlauf 
Date:   Mon Sep 13 19:26:35 2021 +0200

Fortran - fix handling of substring start and end indices

gcc/fortran/ChangeLog:

PR fortran/85130
* expr.c (find_substring_ref): Handle given substring start and
end indices as signed integers, not unsigned.

gcc/testsuite/ChangeLog:

PR fortran/85130
* gfortran.dg/substr_6.f90: Revert commit r8-7574, adding again
test that was erroneously considered as illegal.

(cherry picked from commit 8d93ba93d3b13ac3d3c34404cad87732c809605b)

[Bug fortran/85130] Substrings out of range are not rejected

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

--- Comment #7 from CVS Commits  ---
The master branch has been updated by Harald Anlauf :

https://gcc.gnu.org/g:8d93ba93d3b13ac3d3c34404cad87732c809605b

commit r12-3499-g8d93ba93d3b13ac3d3c34404cad87732c809605b
Author: Harald Anlauf 
Date:   Mon Sep 13 19:26:35 2021 +0200

Fortran - fix handling of substring start and end indices

gcc/fortran/ChangeLog:

PR fortran/85130
* expr.c (find_substring_ref): Handle given substring start and
end indices as signed integers, not unsigned.

gcc/testsuite/ChangeLog:

PR fortran/85130
* gfortran.dg/substr_6.f90: Revert commit r8-7574, adding again
test that was erroneously considered as illegal.

[Bug fortran/85130] Substrings out of range are not rejected

[anlauf at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

--- Comment #6 from anlauf at gcc dot gnu.org ---
Submitted: https://gcc.gnu.org/pipermail/fortran/2021-September/056500.html

[Bug fortran/85130] Substrings out of range are not rejected

[anlauf at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

anlauf at gcc dot gnu.org changed:

   What|Removed |Added

   Assignee|unassigned at gcc dot gnu.org  |anlauf at gcc dot 
gnu.org
 Status|NEW |ASSIGNED

--- Comment #5 from anlauf at gcc dot gnu.org ---
We should handle the substring bounds as signed instead of unsigned.
This is obviously fixed by:

diff --git a/gcc/fortran/expr.c b/gcc/fortran/expr.c
index dfecc3012e1..604e63e6164 100644
--- a/gcc/fortran/expr.c
+++ b/gcc/fortran/expr.c
@@ -1724,8 +1724,8 @@ find_substring_ref (gfc_expr *p, gfc_expr **newp)
   *newp = gfc_copy_expr (p);
   free ((*newp)->value.character.string);

-  end = (gfc_charlen_t) mpz_get_ui (p->ref->u.ss.end->value.integer);
-  start = (gfc_charlen_t) mpz_get_ui (p->ref->u.ss.start->value.integer);
+  end = (gfc_charlen_t) mpz_get_si (p->ref->u.ss.end->value.integer);
+  start = (gfc_charlen_t) mpz_get_si (p->ref->u.ss.start->value.integer);
   if (end >= start)
 length = end - start + 1;
   else


and regtests cleanly.  :-)

@Thomas: although the wording is slightly different between F2003 and F2018, it
always results in length zero if the starting point exceeds the ending point.
Would you agree in reverting your commit r258976 after applying the above?

[Bug fortran/85130] Substrings out of range are not rejected

[anlauf at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

anlauf at gcc dot gnu.org changed:

   What|Removed |Added

   Keywords||wrong-code
 CC||anlauf at gcc dot gnu.org

--- Comment #4 from anlauf at gcc dot gnu.org ---
F2018 has the following changed text in 9.4.1  Substrings:

... If the starting point is greater than the ending point, the substring
has length zero; otherwise, both the starting point and the ending point
shall be within the range 1, 2, ..., n. ...

Thus the following code would be legal:

character(5), parameter :: c0(1) = [ "12345" ]
print *, c0(1)(-5:-8)
end

and print an empty string, while it currently prints junk.

It does the right thing with current trunk when parameter is removed, though.

[Bug fortran/85130] Substrings out of range are not rejected

[dominiq at lps dot ens.fr]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

Dominique d'Humieres  changed:

   What|Removed |Added

   Priority|P4  |P5

[Bug fortran/85130] Substrings out of range are not rejected

[dominiq at lps dot ens.fr]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

Dominique d'Humieres  changed:

   What|Removed |Added

   Priority|P3  |P4
 Status|UNCONFIRMED |NEW
   Last reconfirmed||2018-03-30
 Ever confirmed|0   |1

--- Comment #3 from Dominique d'Humieres  ---
Confirmed.

[Bug fortran/85130] Substrings out of range are not rejected

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

Thomas Koenig  changed:

   What|Removed |Added

 Blocks|84094   |
   Severity|normal  |enhancement

--- Comment #2 from Thomas Koenig  ---
Test suite bug is corrected, the underlying accepts-invalid
is still there.

This is not a constraint, so marking as enhancement.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84094
[Bug 84094] several correctness issues in gfortran.dg

[Bug fortran/85130] Substrings out of range are not rejected

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85130

--- Comment #1 from Thomas Koenig  ---
Author: tkoenig
Date: Fri Mar 30 12:18:30 2018
New Revision: 258976

URL: https://gcc.gnu.org/viewcvs?rev=258976=gcc=rev
Log:
2018-03-30  Thomas Koenig  

PR fortran/85130
* gfortran.dg/substr_6.f90: Remove illegal test for
out-of-bounds substring.


Modified:
trunk/gcc/testsuite/ChangeLog
trunk/gcc/testsuite/gfortran.dg/substr_6.f90