optimization/1544: Optimzation -O3 breaks exception handling

[schmid at snake dot iap dot physik dot tu-darmstadt dot de]

>Number:         1544
>Category:       optimization
>Synopsis:       Optimzation -O3 breaks exception handling
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Jan 03 14:56:03 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Peter Schmid
>Release:        2.97 20010103 (experimental)
>Organization:
TU Darmstadt
>Environment:
System: Linux kiste 2.4.0-test12 #22 Sun Dec 17 17:24:36 CET 2000 i686 unknown
Architecture: i686
GLIBC 2.1.3
GNU assembler version 2.10.91 (i686-pc-linux-gnu) using BFD version 2.10.1.0.4
g++ -v
Reading specs from /usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/specs
Configured with: ../gcc/configure --enable-shared --disable-nls --enable-threads=posix
gcc version 2.97 20010103 (experimental)

host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: ../gcc/configure --enable-shared --disable-nls --enable-threads=posix
>Description:
The following c++ program does not work as expected if the optimization -O3 is
turned on during compilation. Running the program generates a
segmentation fault. If the optimization is reduced to -O2 the program
works as expected.

It did work when the source was compiled by g++-20001220 at the -O3
optimization level. 
>How-To-Repeat:
cat l.C
class A
{
public:
    A() {}
    ~A() {}
};

void f();

int main()
{
    try
    {
        f();
    }
    catch (const char *s) {
    }
}

void f()
{
    A a; 
    throw ("Error");
}
Compiling the program:
g++ -O3 -g -v -o l l.C -save-temps 
Reading specs from /usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/specs
Configured with: ../gcc/configure --enable-shared --disable-nls --enable-threads=posix
gcc version 2.97 20010103 (experimental)
 /usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/cpp0 -lang-c++ -D__GNUG__=2 -D__GXX_ABI_VERSION=100 -v -D__GNUC__=2 -D__GNUC_MINOR__=97 -D__GNUC_PATCHLEVEL__=0 -D__ELF__ -Dunix -Dlinux -D__ELF__ -D__unix__ -D__linux__ -D__unix -D__linux -Asystem=posix -D__OPTIMIZE__ -D__STDC_HOSTED__=1 -g -Acpu=i386 -Amachine=i386 -Di386 -D__i386 -D__i386__ -D__tune_i686__ -D__tune_pentiumpro__ l.C l.ii
GNU CPP version 2.97 20010103 (experimental) (cpplib) (i386 Linux/ELF)
#include "..." search starts here:
#include <...> search starts here:
 /usr/local/include/g++-v3
 /usr/local/i686-pc-linux-gnu/include/g++-v3
 /usr/local/include
 /usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/include
 /usr/local/i686-pc-linux-gnu/include
 /usr/include
End of search list.
 /usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/cc1plus -fpreprocessed l.ii -quiet -dumpbase l.C -g -O3 -version -fnew-abi -o l.s
GNU C++ version 2.97 20010103 (experimental) (i686-pc-linux-gnu) compiled by GNU C version 2.97 20010103 (experimental).
 /usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/../../../../i686-pc-linux-gnu/bin/as -V -Qy -o l.o l.s
GNU assembler version 2.10.91 (i686-pc-linux-gnu) using BFD version 2.10.1.0.4
 /usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/collect2 -m elf_i386 -dynamic-linker /lib/ld-linux.so.2 -o l /usr/lib/crt1.o /usr/lib/crti.o /usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/crtbegin.o -L/usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97 -L/usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/../../../../i686-pc-linux-gnu/lib -L/usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/../../.. l.o -lstdc++ -lm -lgcc -lc -lgcc /usr/local/lib/gcc-lib/i686-pc-linux-gnu/2.97/crtend.o /usr/lib/crtn.o

running the program l
peter@kiste:~ > ./l
Aborted (core dumped)

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This GDB was configured as "i686-pc-linux-gnu"...
(gdb) r
Starting program: /home/peter/l 

Program received signal SIGABRT, Aborted.
0x400d4a71 in __kill () from /lib/libc.so.6
(gdb) bt
#0  0x400d4a71 in __kill () from /lib/libc.so.6
#1  0x400d4745 in raise (sig=6) at ../sysdeps/posix/raise.c:27
#2  0x400d5e0f in abort () at ../sysdeps/generic/abort.c:88
#3  0x40047ccb in __default_terminate () from /usr/local/lib/libstdc++.so.3
#4  0x40047cea in __terminate () from /usr/local/lib/libstdc++.so.3
#5  0x40048b79 in throw_helper () from /usr/local/lib/libstdc++.so.3
#6  0x40048cff in __rethrow (index=0x8049844)
   from /usr/local/lib/libstdc++.so.3
#7  0x804872c in _Z1fv () at l.C:5
#8  0x400cea4e in __libc_start_main (main=0x80486d0 <main>, argc=1, 
    argv=0xbffff8ac, init=0x80484fc <_init>, fini=0x804878c <_fini>, 
    rtld_fini=0x4000aa20 <_dl_fini>, stack_end=0xbffff8a4)
    at ../sysdeps/generic/libc-start.c:92


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