[Bug debug/39372] New: Missing DW_AT_location for constructor static variable

[Bug debug/39372] New: Missing DW_AT_location for constructor static variable

[jan dot kratochvil at redhat dot com]

Regression against g++-4.3 for g++-4.4 on the variable `problem':

g++ (GCC) 4.4.0 20090303 (experimental):
 <1><54>: Abbrev Number: 8 (DW_TAG_subprogram)
    <55>   DW_AT_specification: <0x33>  
    <5a>   DW_AT_inline      : 0        (not inlined)
 <2><72>: Abbrev Number: 11 (DW_TAG_lexical_block)
 <3><73>: Abbrev Number: 12 (DW_TAG_variable)
    <74>   DW_AT_name        : (indirect string, offset: 0x14): problem
    <7a>   DW_AT_type        : <0x85>
(DW_AT_location is not found by any abstract_origin or specificatione etc.)

g++ (GCC) 4.4.0 20090219 (Red Hat 4.4.0-0.21):
 <1><54>: Abbrev Number: 8 (DW_TAG_subprogram)
    <55>   DW_AT_specification: <0x33>
    <5a>   DW_AT_inline      : 0        (not inlined)
 <2><73>: Abbrev Number: 12 (DW_TAG_variable)
    <74>   DW_AT_name        : (indirect string, offset: 0x1a): problem
    <7a>   DW_AT_type        : <0x10b>

it worked before - g++ (GCC) 4.3.2 20081105 (Red Hat 4.3.2-7):
 <1><85>: Abbrev Number: 10 (DW_TAG_subprogram)
    <86>   DW_AT_specification: <0x33>
    <8b>   DW_AT_inline      : 0        (not inlined)
 <2><a3>: Abbrev Number: 13 (DW_TAG_variable)
    <a4>   DW_AT_name        : (indirect string, offset: 0x14): problem
    <aa>   DW_AT_type        : <0x7f>
    <ae>   DW_AT_location    : 9 byte block: 3 8 0 0 0 0 0 0 0  (DW_OP_addr: 8)

-------------------------------------------------------------------------------
extern void f (int *);

class A
{
public:
  A(int i);
};

A::A(int i)
{
  static int *problem = new int(i);
  f (problem);                          
}

void f (int *)
{
}

int
main (void)
{
  A a(42);
  return 0;
}


-- 
           Summary: Missing DW_AT_location for constructor static variable
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jan dot kratochvil at redhat dot com
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] Missing DW_AT_location for constructor static variable

[rguenth at gcc dot gnu dot org]

------- Comment #1 from rguenth at gcc dot gnu dot org  2009-03-05 10:39 -------
It doesn't work with FSF 4.3.3 for me.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |4.3.3 4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3/4.4 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

------- Comment #2 from jakub at gcc dot gnu dot org  2009-03-05 10:54 -------
But in FSF 4.1.2 and 4.2.3 I see:
        .uleb128 0xe    # (DIE (0x161) DW_TAG_variable)
        .ascii "staticvar1\0"   # DW_AT_name
        .byte   0x1     # DW_AT_decl_file (pr39372.C)
        .byte   0xb     # DW_AT_decl_line
        .long   0xe2    # DW_AT_type
        .byte   0x9     # DW_AT_location
        .byte   0x3     # DW_OP_addr
        .quad   _ZZN1AC1EiE10staticvar1

Looking into it.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jakub at gcc dot gnu dot org
                   |dot org                     |
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
      Known to work|                            |4.1.2 4.2.3
   Last reconfirmed|0000-00-00 00:00:00         |2009-03-05 10:54:03
               date|                            |
            Summary|Missing DW_AT_location for  |[4.3/4.4 Regression] Missing
                   |constructor static variable |DW_AT_location for
                   |                            |constructor static variable
   Target Milestone|---                         |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3/4.4 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

------- Comment #3 from jakub at gcc dot gnu dot org  2009-03-05 11:14 -------
Ah, the reason why it didn't fail with 4.1.x and older 4.2.x/4.3.x is
PR27574.  Before that change set_decl_abstract_flags saw error_mark_node
DECL_INITIAL and so didn't dive into the blocks, now it does.

Guess the right fix will be not mark TREE_STATIC VAR_DECLs in
set_block_abstract_flags as abstract.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3/4.4 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

------- Comment #4 from jakub at gcc dot gnu dot org  2009-03-05 15:02 -------
This is harder than I thought.
My first attempt:
--- integrate.c.xx2009-02-20 15:36:24.000000000 +0100
+++ integrate.c2009-03-05 15:46:23.000000000 +0100
@@ -173,7 +173,10 @@ set_block_abstract_flags (tree stmt, int
   for (local_decl = BLOCK_VARS (stmt);
        local_decl != NULL_TREE;
        local_decl = TREE_CHAIN (local_decl))
-    set_decl_abstract_flags (local_decl, setting);
+    /* Don't mark local static variables, those are shared between all
+       inline/cloned copies.  */
+    if (TREE_CODE (local_decl) != VAR_DECL || !TREE_STATIC (local_decl))
+      set_decl_abstract_flags (local_decl, setting);

   for (subblock = BLOCK_SUBBLOCKS (stmt);
        subblock != NULL_TREE;

works well for this testcase, the abstract DIE has DW_AT_location attribute for
the local variable and DIEs for the ctor clones don't have any DIEs for this
variable.  But it creates worse output for C:
extern void f (int *);
static inline __attribute__((always_inline)) void foo (void)
{
  static int staticvar1[4];
  f (staticvar1);
}

void bar (void)
{
  foo ();
}

void baz (void)
{
  foo ();
  foo ();
}

Before the patch the abstract fn DIE contains a DIE for the static variable
without DW_AT_location and the spots that inline this fn has DIE for the static
variable with DW_AT_abstract_origin and DW_AT_location (the same in all cases).
After the patch the abstract fn DIE's static variable DIE contains
DW_AT_location, the spots that inline this have DIE for the static variable
without DW_AT_abstract_origin and again with DW_AT_location.  I'd say either
the abstract origin DIE shouldn't contain DW_AT_location, but then all spots
that use it should contain DW_AT_abstract_origin and DW_AT_location, or the
abstract origin DIE should contain DW_AT_location and the clones shouldn't
contain the DIE at all.  So, I've tried a different patch:

--- tree-cfg.c.jj2        2009-03-05 09:44:31.000000000 +0100
+++ tree-cfg.c        2009-03-05 14:57:46.000000000 +0100
@@ -1799,11 +1799,11 @@ remove_useless_stmts_bind (gimple_stmt_i
       tree var = NULL_TREE;
       /* Even if there are no gimple_bind_vars, there might be other
          decls in BLOCK_VARS rendering the GIMPLE_BIND not useless.  */
-      if (block)
+      if (block && !BLOCK_NUM_NONLOCALIZED_VARS (block))
         for (var = BLOCK_VARS (block); var; var = TREE_CHAIN (var))
           if (TREE_CODE (var) == IMPORTED_DECL)
             break;
-      if (var)
+      if (var || (block && BLOCK_NUM_NONLOCALIZED_VARS (block)))
         gsi_next (gsi);
       else
         {

which prevents removing GIMPLE_BINDs that contain BLOCK_NONLOCALIZED_VARS in
its gimple_bind_block (tree-ssa-live.c BLOCK removal does the same thing).
Unfortunately this doesn't solve the original bug, because the abstract
FUNCTION_DECL in the C++ ctor clone case is marked DECL_ABSTRACT already by the
C++ FE, so when dwarf2out_abstract_function is called on it, was_abstract is
true and so everything is set to DECL_ABSTRACT, but not reset afterwards.
This means the VAR_DECL in clone's BLOCK_NONLOCALIZED_VARS has DECL_ABSTRACT
set and thus won't have DW_AT_location emitted.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hubicka at gcc dot gnu dot
                   |                            |org
         AssignedTo|jakub at gcc dot gnu dot org|unassigned at gcc dot gnu
                   |                            |dot org
             Status|ASSIGNED                    |NEW


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3/4.4 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

------- Comment #5 from jakub at gcc dot gnu dot org  2009-03-06 09:46 -------
Created an attachment (id=17404)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=17404&action=view)
gcc44-pr39372.patch

Patch I'm going to bootstrap/regtest.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jakub at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3/4.4 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

------- Comment #6 from jakub at gcc dot gnu dot org  2009-03-06 22:49 -------
Subject: Bug 39372

Author: jakub
Date: Fri Mar  6 22:49:39 2009
New Revision: 144682

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=144682
Log:
        PR debug/39372
        * dwarf2out.c (add_abstract_origin_attribute): Return
        origin_die.
        (gen_variable_die): Emit DW_AT_location on abstract static variable's
        DIE, don't emit it if abstract origin already has it.
        * tree-cfg.c (remove_useless_stmts_bind): GIMPLE_BINDs with any
        BLOCK_NONLOCALIZED_VARS in its gimple_bind_block aren't useless.

        * g++.dg/debug/dwarf2/static-local-var-in-ctor.C: New test.

Added:
    trunk/gcc/testsuite/g++.dg/debug/dwarf2/static-local-var-in-ctor.C
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/dwarf2out.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-cfg.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

------- Comment #7 from jakub at gcc dot gnu dot org  2009-03-06 22:52 -------
Fixed on the trunk so far.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|4.3.3 4.4.0                 |4.3.3
      Known to work|4.1.2 4.2.3                 |4.1.2 4.2.3 4.4.0
            Summary|[4.3/4.4 Regression] Missing|[4.3 Regression] Missing
                   |DW_AT_location for          |DW_AT_location for
                   |constructor static variable |constructor static variable


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.4.0                       |4.4.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.4.1                       |4.4.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.4.2                       |4.4.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.4.3                       |4.4.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu dot org]

-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.4.4                       |4.4.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

[Bug debug/39372] [4.3 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
      Known to work|                            |
         Resolution|                            |FIXED

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-03-13 13:10:38 UTC ---
Fixed.

[Bug debug/39372] [4.3 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.4.6                       |4.4.7

[Bug debug/39372] [4.3 Regression] Missing DW_AT_location for constructor static variable

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39372

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.4.5                       |4.4.6