--- Additional Comments From ro at techfak dot uni-bielefeld dot de
2005-07-05 17:04 ---
Subject: Re: [4.0/4.1 Regression] Cannot build gnattools on Tru64 UNIX V5.1B
charlet at gcc dot gnu dot org writes:
Given your last comment (a variable set to 4), it still looks very much like
a codegen issue to me, and likely target dependent.
I guess a next step could be to either look at the ssa transformations
performed,
and/or at the assembly code generated for the elab routine.
I've approached this a bit differently:
* I tried to bootstrap mainline with -O0, but it failed as before and even
an almost current CVS gdb just SEGVs on the gnatmake binary ;-(
* On the 4.0 branch, a bootstrap with -O0 also failed as before, but at
least I can debug the gnatmake binary:
osint__running_programs starts as 0, is later initialized to 2
(osint__make) in osint__set_program and again overwritten to 4
(osint__unspecified) in osint___elabb:
Breakpoint 4, osint.set_program (p=16) at
/vol/gnu/src/gcc/gcc-4.0-branch-dist/gcc/ada/osint.adb:2274
(gdb) p osint__running_program
$6 = 0
(gdb) where
#0 osint.set_program (p=16) at
/vol/gnu/src/gcc/gcc-4.0-branch-dist/gcc/ada/osint.adb:2274
#1 0x0001201fbf10 in osint__m___elabb () at
/vol/gnu/src/gcc/gcc-4.0-branch-dist/gcc/ada/osint-m.adb:49
#2 0x0001200b7750 in adainit () at b_gnatm.c:562
#3 0x0001200b8aec in main (argc=536854608, argv=0x0, envp=0x0) at
b_gnatm.c:733
#4 0x0001200b617c in __start ()
(gdb) cont
Continuing.
Watchpoint 6: {data variable, no debug info} 5369590752
Old value = 0
New value = 2
osint.set_program (p=16) at
/vol/gnu/src/gcc/gcc-4.0-branch-dist/gcc/ada/osint.adb:2280
(gdb) cont
Continuing.
Breakpoint 3, osint___elabb () at
/vol/gnu/src/gcc/gcc-4.0-branch-dist/gcc/ada/osint.adb:45
(gdb) cont
Continuing.
Watchpoint 6: {data variable, no debug info} 5369590752
Old value = 2
New value = 4
osint___elabb () at /vol/gnu/src/gcc/gcc-4.0-branch-dist/gcc/ada/osint.adb:48
(gdb) where
#0 osint___elabb () at
/vol/gnu/src/gcc/gcc-4.0-branch-dist/gcc/ada/osint.adb:48
#1 0x0001200b7cc0 in adainit () at b_gnatm.c:610
#2 0x0001200b8aec in main (argc=536854608, argv=0x0, envp=0x0) at
b_gnatm.c:733
#3 0x0001200b617c in __start ()
* On the 3.4 branch, osint__running_program is statically initialized to
osint__unspecified in osint.adb, later reset to osint__make in
osint__set_program:
Old value = {F = osint__unspecified}
New value = {F = osint__make}
osint__set_program (p=osint__make) at
/vol/gnu/src/gcc/gcc-3.4-branch-dist/gcc/ada/osint.adb:2253
Breakpoint 3, osint.set_program (p=osint__make) at
/vol/gnu/src/gcc/gcc-3.4-branch-dist/gcc/ada/osint.adb:2247
(gdb) where
#0 osint.set_program (p=osint__make) at
/vol/gnu/src/gcc/gcc-3.4-branch-dist/gcc/ada/osint.adb:2247
#1 0x00012019efe8 in osint__m___elabb () at
/vol/gnu/src/gcc/gcc-3.4-branch-dist/gcc/ada/osint-m.adb:49
#2 0x0001200a046c in adainit () at b_gnatm.c:267
#3 0x0001200a11c0 in main (argc=6, argv=0x11fffc018, envp=0x11fffc050) at
b_gnatm.c:389
#4 0x00012009fc3c in __start ()
$1 = {F = osint__unspecified}
(gdb) cont
Continuing.
Watchpoint 5: osint.running_program
Old value = {F = osint__unspecified}
New value = {F = osint__make}
osint.set_program (p=osint__make) at
/vol/gnu/src/gcc/gcc-3.4-branch-dist/gcc/ada/osint.adb:2253
Thus, the way/order of initialization changed between 3.4 and 4.0, causing
the observed failure:
* from osint.adb:
package body Osint is
Running_Program : Program_Type := Unspecified;
-- comment required here ???
* from osint-m.adb:
package body Osint.M is
[...]
begin
Set_Program (Make);
end Osint.M;
* in 3.4:
osint__running_program = osint__unspecified (4) statically (osint.o)
osint__running_program = osint__make (2) in osint.set_program, called
from osint__m___elabb (osint_m.o)
* in 4.0:
osint__running_program = 0 statically (osint.o)
osint__running_program = osint__make (2) in osint.set_program, called from
osint__m___elabb (osint_m.o)
osint__running_program = osint__unspecified (4) in osint___elabb (osint.o)
Hope this helps to narrow down the root cause.
Rainer
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18434
