objc/2902: collect2 doesn't find ctors/dtors in shared libraries under hpux10.20

[dave.anglin@nrc.ca]

>Number:         2902
>Category:       objc
>Synopsis:       collect2 doesn't find ctors/dtors in shared libraries under hpux10.20
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue May 22 11:46:00 PDT 2001
>Closed-Date:
>Last-Modified:
>Originator:     Dave Anglin
>Release:        gcc version 3.0 20010518 (prerelease)
>Organization:
>Environment:
# ../../gcc/configure  --host=hppa1.1-hp-hpux10.20 --target=hppa1.1-hp-hpux10.20 --srcdir=../../gcc --with-gcc-version-trigger=/xxx/gnu/gcc-3.0/gcc/version.c --with-gnu-as --enable-shared --enable-threads --enable-debug=no
>Description:
The symptom is a large number of failures in the testsuite with the following error:

Executing on host: /xxx/gnu/gcc-3.0/objdir/gcc/xgcc -B/xxx/gnu/gcc-3.0/objdir/gcc/ /xxx/gnu/gcc-3.0/gcc/testsuite/objc/execute/_cmd.m  -w  -O  -I/xxx/gnu/gcc-3.0/gcc/testsuite/../../libobjc -L/xxx/gnu/gcc-3.0/objdir/hppa1.1-hp-hpux10.20/libobjc/.libs  -lobjc -lm   -fPIC -o /xxx/gnu/gcc-3.0/objdir/gcc/testsuite/_cmd.x
  (timeout = 300)
PASS: objc/execute/_cmd.m compilation,  -O
objc runtime: cannot find class Object
FAIL: objc/execute/_cmd.m execution,  -O

In debugging this, I found that the constructors to build the
classes Object and NXConstantString don't run when the application
is linked with a shared libobjc.  This is apparently because
collect2 can't determine that these constructors are needed.
Here is part of the output generated by collect2 with `-debug'
linking _cmd.x:

/usr/ccs/bin/ld -L/lib/pa1.1 -L/usr/lib/pa1.1 -z -u main -o /xxx/gnu/gcc-3.0/objdir/gcc/testsuite/_cmd.x /usr/ccs/lib/crt0.o -L/xxx/gnu/gcc-3.0/objdir/hppa1.1-hp-hpux10.20/libobjc/.libs -L/xxx/gnu/gcc-3.0/objdir/gcc -L/usr/local/lib/gcc-lib/hppa1.1-hp-hpux10.20/3.0 -L/usr/ccs/bin -L/usr/ccs/lib -L/opt/langtools/lib -L/usr/local/lib/gcc-lib/hppa1.1-hp-hpux10.20/3.0/../../.. /var/tmp/ccapeMug.o -lobjc -lm -lgcc -lc -lgcc
 /usr/local/lib/gcc-lib/hppa1.1-hp-hpux10.20/3.0/../../../../hppa1.1-hp-hpux10.20/bin/nm -n /xxx/gnu/gcc-3.0/objdir/gcc/testsuite/_cmd.x

nm output with constructors/destructors.
        000025e8 T _GLOBAL__I_main

 /usr/ccs/bin/chatr /xxx/gnu/gcc-3.0/objdir/gcc/testsuite/_cmd.x

ldd output with constructors/destructors.
                     dynamic   /xxx/gnu/gcc-3.0/objdir/hppa1.1-hp-hpux10.20/libobjc/.libs/libobjc.sl.1
                     dynamic   /usr/lib/libc.1

 /usr/local/lib/gcc-lib/hppa1.1-hp-hpux10.20/3.0/../../../../hppa1.1-hp-hpux10.20/bin/nm -n /xxx/gnu/gcc-3.0/objdir/hppa1.1-hp-hpux10.20/libobjc/.libs/libobjc.sl.1

nm output with constructors/destructors.
        00017aa0 T _GLOBAL__I___objc_linking
        00017ad0 T _GLOBAL__I___objc_linking
        00018210 T _GLOBAL__I_.._.._.._libobjc_NXConstStr.mSFndDa
        00018228 T _GLOBAL__I_.._.._.._libobjc_NXConstStr.mSFndDa
        0001a1e0 T _GLOBAL__I_.._.._.._libobjc_Object.mOXKa8a
        0001a1f8 T _GLOBAL__I_.._.._.._libobjc_Object.mOXKa8a
        0001b058 T _GLOBAL__I_.._.._.._libobjc_Protocol.mxvicuc
        0001b070 T _GLOBAL__I_.._.._.._libobjc_Protocol.mxvicuc

 /usr/local/lib/gcc-lib/hppa1.1-hp-hpux10.20/3.0/../../../../hppa1.1-hp-hpux10.2
0/bin/nm -n /usr/lib/libc.1

nm output with constructors/destructors.

1 constructor(s) found
0 destructor(s)  found
0 frame table(s) found
[Leaving /xxx/gnu/gcc-3.0/objdir/gcc/testsuite/_cmd.x]
>How-To-Repeat:
Configure with `--enable-shared'.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: