[Bug c/36047] New: -pg does not work on large binaries and m68k

[Bug c/36047] New: -pg does not work on large binaries and m68k

[gcc at breakpoint dot cc]

bigeasy@ayoka:~/cc$ echo 'int main(void) { return 0; }' > file.c
bigeasy@ayoka:~/cc$ m68k-linux-gnu-gcc -o file file.c -static -pg
/tmp/ccw33VYP.o: In function `main':
file.c:(.text+0x6): relocation truncated to fit: R_68K_PC16 against `.data'
collect2: ld returned 1 exit status

It works fine with a small binary (without -static).
I don't really know what the label is used for. I patched my gcc with:
|--- a/gcc/config/m68k/linux.h
|+++ b/gcc/config/m68k/linux.h
|@@ -143,7 +143,6 @@ along with GCC; see the file COPYING3.
| #undef FUNCTION_PROFILER
| #define FUNCTION_PROFILER(FILE, LABELNO) \
| {                                                                 \
|-  asm_fprintf (FILE, "\tlea (%LLP%d,%Rpc),%Ra1\n", (LABELNO));            \
|   if (flag_pic)                                                           \
|     fprintf (FILE, "\tbsr.l _mcount@PLTPC\n");                            \
|   else                                                                    \
|--- a/gcc/config/m68k/m68k.h
|+++ b/gcc/config/m68k/m68k.h
|@@ -576,7 +576,7 @@ extern enum reg_class regno_reg_class[];
| #define FUNCTION_ARG(CUM, MODE, TYPE, NAMED) 0
|
| #define FUNCTION_PROFILER(FILE, LABELNO)  \
|-  asm_fprintf (FILE, "\tlea %LLP%d,%Ra0\n\tjsr mcount\n", (LABELNO))
|+  asm_fprintf (FILE, "\tjsr mcount\n", (LABELNO))
|
| #define EXIT_IGNORE_STACK 1
|

I'm not using glibc's mcount function but my own in which I unwind the stack in
order to obtain caller's address (that's the purpose of the label I guess).

I checked gcc-core-4.3.0.tar.bz2 and the two lea lines are unchanged so the bug
should be still there. 

Now how do we fix this? Removing the label or allowing larger distances?


-- 
           Summary: -pg does not work on large binaries and m68k
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: gcc at breakpoint dot cc
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: m68k-uclinux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36047

[Bug target/36047] -pg does not work on large binaries and m68k

[gcc at breakpoint dot cc]

------- Comment #1 from gcc at breakpoint dot cc  2008-07-24 19:48 -------
Does anybody care about this bug?


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36047

[Bug target/36047] -pg does not work on large binaries and m68k

[mkuvyrkov at gcc dot gnu dot org]

------- Comment #2 from mkuvyrkov at gcc dot gnu dot org  2009-03-16 11:35 -------
Would you please attach a preprocessed testcase so one can reproduce the
problem.


-- 

mkuvyrkov at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |mkuvyrkov at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36047

[Bug target/36047] -pg does not work on large binaries and m68k

[gcc at breakpoint dot cc]

------- Comment #3 from gcc at breakpoint dot cc  2009-04-22 18:41 -------
Wasn't 

# echo 'int main(void) { return 0; }' > file.c

not enough or did you overlook that part? 

The -E output is pretty much the same, it is:

$ cat test.i 
# 1 "test.c"
# 1 "<built-in>"
# 1 "<command-line>"
# 1 "test.c"
int main(void)
{
 return 0;
}


---
The -S output (I guess you meant that) would be:

$ m68k-linux-gnu-gcc -o test.S test.c -static -pg -S && cat test.S 
#NO_APP
        .file   "test.c"
        .text
        .align  2
        .globl  main
        .type   main, @function
main:
        link.w %fp,#0
        .data
        .align  2
.LP2:
        .long   0
        .text
        lea (.LP2,%pc),%a1
        jbsr _mcount
        clr.l %d0
        unlk %fp
        rts
        .size   main, .-main
        .ident  "GCC: (Sourcery G++ Lite 4.3-43) 4.3.2"
        .section        .note.GNU-stack,"",@progbits
---- 

And my rec for the fix was to get rid of the lea before the branch to the
_mcount call. However someone might need it, I'm not sure.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36047

[Bug target/36047] -pg does not work on large binaries and m68k

[mkuvyrkov at gcc dot gnu dot org]

------- Comment #4 from mkuvyrkov at gcc dot gnu dot org  2009-11-04 16:57 -------
It appears that 'lea' serves some compatibility purpose.  The code is there
since 1995.

Recent GLIBC defines _mcount as
void
_mcount (void)
{
  mcount_internal ((u_long)
                   __builtin_extract_return_addr (__builtin_return_address
                                                  (1)),
                   (u_long)
                   __builtin_extract_return_addr (__builtin_return_address
                                                  (0)));
}
so the value of %a1 is unused.  Newlib and uClibc don't define _mcount for m68k
at all.

Andreas, I suggest simply removing the 'lea'; they seem to be no users for it.

Alternatively, for the !PIC case we may use 'lea <label>, %a1' (no pc-relative
relocation) and for the PIC case use a longer sequence, something like: 'move.l
#<label>@PC32, %a1\n add.l (-4, %pc), %a1'.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36047

[Bug target/36047] -pg does not work on large binaries and m68k

[mkuvyrkov at gcc dot gnu dot org]

------- Comment #5 from mkuvyrkov at gcc dot gnu dot org  2009-11-19 10:09 -------
gcc@breakpoint.cc,

Would you please submit your patch to gcc-patches@gcc.gnu.org.  Only the
linux.h version of FUNCTION_PROFILER causes problems, you can leave the m68k.h
version as is.

Thanks.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36047

[Bug target/36047] -pg does not work on large binaries and m68k

[mkuvyrkov at gcc dot gnu dot org]

------- Comment #6 from mkuvyrkov at gcc dot gnu dot org  2009-12-11 15:32 -------
Subject: Bug 36047

Author: mkuvyrkov
Date: Fri Dec 11 15:32:08 2009
New Revision: 155165

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=155165
Log:
2009-12-11  Sebastian Andrzej Siewior  <bigeasy@linutronix.de>

        PR target/36047

        * config/m68k/linux.h: Remove LABELNO from the mcount statement. It is
        not used by glibc/uclibc and does not work with large binaries.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/m68k/linux.h


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36047

[Bug target/36047] -pg does not work on large binaries and m68k

[mkuvyrkov at gcc dot gnu dot org]

------- Comment #7 from mkuvyrkov at gcc dot gnu dot org  2009-12-11 15:35 -------
This is now fixed with the above patch by Sebastian.


-- 

mkuvyrkov at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36047