[Bug debug/63300] New: 'const volatile' sometimes stripped in debug info

[Bug debug/63300] New: 'const volatile' sometimes stripped in debug info

[arnez at linux dot vnet.ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63300

            Bug ID: 63300
           Summary: 'const volatile' sometimes stripped in debug info
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
          Assignee: unassigned at gcc dot gnu.org
          Reporter: arnez at linux dot vnet.ibm.com

With current upstream gcc, the following commands do not yield the expected
output:

echo 'void f (const volatile int x) { }' | gcc -xc -c -g -o foo.o -
readelf -wi foo.o | grep 'volatile\|const'

With an older gcc we get something like this:

 <1><54>: Abbrev Number: 4 (DW_TAG_const_type)
 <1><59>: Abbrev Number: 5 (DW_TAG_volatile_type)

With the current gcc we get nothing.  Indeed, the resulting debug info declares
the parameter 'x' merely as an 'int' instead of 'const volatile int'.

The same happens with some other combinations as well, e.g.:

char *const volatile x
const volatile float x
const volatile int *x

[Bug debug/63300] 'const volatile' sometimes stripped in debug info

[mark at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63300

--- Comment #2 from Mark Wielaard <mark at gcc dot gnu.org> ---
Sorry about that. I added an explicit testcases
(gcc/testsuite/gcc.dg/guality/const-volatile.c and
gcc/testsuite/gcc.dg/guality/restrict.c) explicitly to catch such issue. But
apparently they didn't trigger this particular case.

[Bug debug/63300] 'const volatile' sometimes stripped in debug info

[mark at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63300

Mark Wielaard <mark at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |mark at gcc dot gnu.org

--- Comment #3 from Mark Wielaard <mark at gcc dot gnu.org> ---
Proposed fix: https://gcc.gnu.org/ml/gcc-patches/2014-09/msg01723.html

[Bug debug/63300] 'const volatile' sometimes stripped in debug info

[krebbel at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63300

--- Comment #4 from Andreas Krebbel <krebbel at gcc dot gnu.org> ---
Author: krebbel
Date: Thu Sep 25 07:37:36 2014
New Revision: 215582

URL: https://gcc.gnu.org/viewcvs?rev=215582&root=gcc&view=rev
Log:
2014-09-25  Andreas Arnez  <arnez@linux.vnet.ibm.com>

    PR 63300/debug
    * tree.c (check_base_type): New.
    (check_qualified_type): Exploit new helper function above.
    * tree.h (check_base_type): New prototype.
    * dwarf2out.c (get_nearest_type_subqualifiers): New.
    (modified_type_die): Fix handling for qualifiers.  Qualifiers to
    "peel off" are now determined using get_nearest_type_subqualifiers.

2014-09-25  Mark Wielaard  <mjw@redhat.com>

    PR 63300/debug
    * gcc.dg/debug/dwarf2/stacked-qualified-types-1.c: New testcase.
    * gcc.dg/debug/dwarf2/stacked-qualified-types-2.c: Likewise.
    * gcc.dg/guality/pr63300-const-volatile.c: New testcase.



Added:
    trunk/gcc/testsuite/gcc.dg/debug/dwarf2/stacked-qualified-types-1.c
    trunk/gcc/testsuite/gcc.dg/debug/dwarf2/stacked-qualified-types-2.c
    trunk/gcc/testsuite/gcc.dg/guality/pr63300-const-volatile.c
Modified:
    trunk/gcc/dwarf2out.c
    trunk/gcc/tree.c
    trunk/gcc/tree.h

[Bug debug/63300] 'const volatile' sometimes stripped in debug info

[arnez at linux dot vnet.ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63300

Andreas Arnez <arnez at linux dot vnet.ibm.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #5 from Andreas Arnez <arnez at linux dot vnet.ibm.com> ---
The fix works and I didn't find any regressions.

[Bug debug/63300] 'const volatile' sometimes stripped in debug info

[arnez at linux dot vnet.ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63300

Andreas Arnez <arnez at linux dot vnet.ibm.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |CLOSED

--- Comment #6 from Andreas Arnez <arnez at linux dot vnet.ibm.com> ---
Closing per comment #5.