[Bug fortran/35154] New: Unable to reference symbols in Fortran COMMON due to .stabs format

[Bug fortran/35154] New: Unable to reference symbols in Fortran COMMON due to .stabs format

[george at gly dot bris dot ac dot uk]

Problem is fixed with approved (but uncommitted) patch at

http://gcc.gnu.org/ml/gcc-patches/2008-02/msg00286.html

Arises on different systems lacking either: 1) loader ability to process
external (i.e. non-.TEXT) SYMBOL+offset in .stabs; or 2) gdb ability to process
same.  Darwin is one; FX Coudert's gfortran
testing system is another (unknown type).

To replicate, see below.
----------------
#cat simtest.f
      common i,j
      common /label/l,m
      i = 1
      j = 2
      k = 3
      l = 4
      m = 5
      call sub
      end
      subroutine sub
      common /label/l,m
      logical first
      save n
      data first /.true./
      if (first) then
         n = 0
         first = .false.
      endif
      n = n + 1
      l = l + 1
      end
#
#gfortran -v -g -o simtest simtest.f
Driving: gfortran -mmacosx-version-min=10.4 -v -g -o simtest simtest.f
-lgfortranbegin -lgfortran -shared-libgcc
Using built-in specs.
Target: powerpc-apple-darwin8.8.0
Configured with: ../gcc-trunk/gcc/configure --enable-languages=c,fortran
Thread model: posix
gcc version 4.3.0 20080204 (experimental) (GCC) 
COLLECT_GCC_OPTIONS='-mmacosx-version-min=10.4' '-v' '-g' '-o' 'simtest'
'-shared-libgcc'
 /usr/local/libexec/gcc/powerpc-apple-darwin8.8.0/4.3.0/f951 simtest.f
-ffixed-form -feliminate-unused-debug-symbols -fPIC -quiet -dumpbase simtest.f
-mmacosx-version-min=10.4 -auxbase simtest -g -version -fintrinsic-modules-path
/usr/local/lib/gcc/powerpc-apple-darwin8.8.0/4.3.0/finclude -o
/var/tmp//cc6Ld1Df.s
GNU F95 (GCC) version 4.3.0 20080204 (experimental) (powerpc-apple-darwin8.8.0)
        compiled by GNU C version 4.3.0 20080204 (experimental), GMP version
4.2.2, MPFR version 2.3.0-p3.
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
COLLECT_GCC_OPTIONS='-mmacosx-version-min=10.4' '-v' '-g' '-o' 'simtest'
'-shared-libgcc'
 as -arch ppc -o /var/tmp//ccILL0ce.o /var/tmp//cc6Ld1Df.s
COMPILER_PATH=/usr/local/libexec/gcc/powerpc-apple-darwin8.8.0/4.3.0/:/usr/local/libexec/gcc/powerpc-apple-darwin8.8.0/4.3.0/:/usr/local/libexec/gcc/powerpc-apple-darwin8.8.0/:/usr/local/lib/gcc/powerpc-apple-darwin8.8.0/4.3.0/:/usr/local/lib/gcc/powerpc-apple-darwin8.8.0/
LIBRARY_PATH=/usr/local/lib/gcc/powerpc-apple-darwin8.8.0/4.3.0/:/usr/local/lib/gcc/powerpc-apple-darwin8.8.0/4.3.0/../../../:/usr/lib/
COLLECT_GCC_OPTIONS='-mmacosx-version-min=10.4' '-v' '-g' '-o' 'simtest'
'-shared-libgcc'
 /usr/local/libexec/gcc/powerpc-apple-darwin8.8.0/4.3.0/collect2 -dynamic -arch
ppc -macosx_version_min 10.4 -multiply_defined suppress
-weak_reference_mismatches non-weak -o simtest -lcrt1.o
/usr/local/lib/gcc/powerpc-apple-darwin8.8.0/4.3.0/crt3.o
-L/usr/local/lib/gcc/powerpc-apple-darwin8.8.0/4.3.0
-L/usr/local/lib/gcc/powerpc-apple-darwin8.8.0/4.3.0/../../..
/var/tmp//ccILL0ce.o -lgfortranbegin -lgfortran -lgcc_s.10.4 -lgcc
-lSystemStubs -lSystem
COLLECT_GCC_OPTIONS='-mmacosx-version-min=10.4' '-v' '-g' '-o' 'simtest'
'-shared-libgcc'

#gdb simtest
GNU gdb 6.3.50-20050815 (Apple version gdb-573) (Fri Oct 20 15:54:33 GMT 2006)
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "powerpc-apple-darwin"...Reading symbols for shared
libraries .... done

(gdb) l MAIN__ 
1             common i,j
2             common /label/l,m
3             i = 1
4             j = 2
5             k = 3
6             l = 4
7             m = 5
8             call sub
9             end
10            subroutine sub
(gdb) break 8
Breakpoint 1 at 0x2c28: file simtest.f, line 8.
(gdb) run
Starting program: /Users/george/f77/simtest 
Reading symbols for shared libraries ..+. done

Breakpoint 1, MAIN__ () at simtest.f:8
8             call sub
(gdb) p i
Address of symbol "i" is unknown.
(gdb) p j
No symbol "j" in current context.
(gdb) p k
$1 = 3
Current language:  auto; currently fortran
(gdb) p l
Address of symbol "l" is unknown.
(gdb) p m
No symbol "m" in current context.
(gdb) quit
The program is running.  Exit anyway? (y or n) y
#
-------------------


-- 
           Summary: Unable to reference symbols in Fortran COMMON due to
                    .stabs format
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: george at gly dot bris dot ac dot uk
 GCC build triplet: powerpc-apple-darwin8.8.0
  GCC host triplet: powerpc-apple-darwin8.8.0 (and others)
GCC target triplet: powerpc-apple-darwin8.8.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35154

[Bug fortran/35154] Unable to reference symbols in Fortran COMMON due to .stabs format

[george at gcc dot gnu dot org]

-- 

george at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |george at gcc dot gnu dot
                   |dot org                     |org
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2008-02-14 09:09:32
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35154

[Bug fortran/35154] Unable to reference symbols in Fortran COMMON due to .stabs format

[george at gcc dot gnu dot org]

------- Comment #1 from george at gcc dot gnu dot org  2008-04-02 08:01 -------
Fixed in rev 133800 1 April 2008


-- 

george at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35154

[Bug fortran/35154] Unable to reference symbols in Fortran COMMON due to .stabs format

[jvdelisle at gcc dot gnu dot org]

------- Comment #2 from jvdelisle at gcc dot gnu dot org  2008-04-19 06:49 -------
Reopening this PR after reverting the patch until the problem can be sorted
out.

See PR35892 which caused by the patch to this one.


-- 

jvdelisle at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35154

[Bug fortran/35154] Unable to reference symbols in Fortran COMMON due to .stabs format

[george at gcc dot gnu dot org]

------- Comment #3 from george at gcc dot gnu dot org  2008-04-26 09:46 -------
Subject: Bug 35154

Author: george
Date: Sat Apr 26 09:46:01 2008
New Revision: 134696

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=134696
Log:
2008-04-26  George Helffrich <george@gcc.gnu.org>

        PR fortran/35892
        PR fortran/35154
        * fortran/trans-common.c (create_common):  Add decl to function
        chain (if inside one) to preserve identifier scope in debug output.

        * testsuite/gfortran.dg/debug/pr35154-stabs.f:  New test case for
        .stabs functionality.
        * testsuite/gfortran.dg/debug/pr35154-dwarf2.f:  New test case for
        DWARF functionality.


Added:
    trunk/gcc/testsuite/gfortran.dg/debug/pr35154-dwarf2.f
    trunk/gcc/testsuite/gfortran.dg/debug/pr35154-stabs.f
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/trans-common.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35154

[Bug fortran/35154] Unable to reference symbols in Fortran COMMON due to .stabs format

[george at gcc dot gnu dot org]

------- Comment #4 from george at gcc dot gnu dot org  2008-04-26 10:14 -------
Reworked patch committed as rev. 134696.


-- 

george at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35154

[Bug fortran/35154] Unable to reference symbols in Fortran COMMON due to .stabs format

[dominiq at lps dot ens dot fr]

------- Comment #5 from dominiq at lps dot ens dot fr  2008-09-01 09:37 -------
On i686-apple-darwin9, I have the following failures in both 32 and 64 bit
modes:

FAIL: gfortran.dg/debug/pr35154-dwarf2.f -gdwarf-2 scan-assembler DW_AT_name:
"__BLNK__"
FAIL: gfortran.dg/debug/pr35154-dwarf2.f -gdwarf-2 scan-assembler DW_AT_name:
"label"

Looking at the assembly code I see:

...
        .ascii "__BLNK__\0"     # DW_AT_name
        .ascii "i\0"    # DW_AT_name
        .ascii "j\0"    # DW_AT_name
        .ascii "label\0"        # DW_AT_name
...

I thing that changing

C { dg-final { scan-assembler "DW_AT_name: \"__BLNK__\"" } }
C { dg-final { scan-assembler "DW_AT_name: \"label\"" } }

with

C { dg-final { scan-assembler "DW_AT_name: \"__BLNK__.*\"" } }
C { dg-final { scan-assembler "DW_AT_name: \"label.*\"" } }

will fix the failures.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35154