I have a function f() which throws
an exception of the type Exception:
class Exception {
};
extern "C" void f() {
throw Exception();
}
The exception should be catched with
try { f(); }
catch (Exception& e) .
This works not if f() is placed in
a shared library and the library was
loaded with dlopen(). If the type of the
exception is a class then this type
seems to be missing and it can't be determind
which handler can catch the exception. Only
catch (...) works. Other types, e. g. int,
works fine.
The bug occurs on (1) Linux / gcc 3.4.0,
(2) Linux gcc 3.3.2 but not on (3) Solaris /
gcc 3.3.2.
(1)
>Release: 3.4.0
>Environment:
System: Linux mars 2.4.21-99-smp #1 SMP Wed Sep 24 13:31:14 UTC 2003 i686 i686
i386 GNU/Linux
Architecture: i686
<machine, os, target, libraries (multiple lines)>
host: i586-suse-linux-gnu
build: i586-suse-linux-gnu
target: i586-suse-linux-gnu
configured with: /tmp/1/GCC340/gcc-3.4.0/configure --enable-threads=posix
--prefix=/usr/gcc340 --enable-languages=c,c++,f77,objc,java,ada
--disable-checking --enable-libgcj --with-system-zlib --enable-shared
--enable-__cxa_atexit i586-suse-linux
(2)
>Release: 3.3.2
>Environment:
System: Linux mars 2.4.21-99-smp #1 SMP Wed Sep 24 13:31:14 UTC 2003 i686 i686
i386 GNU/Linux
Architecture: i686
<machine, os, target, libraries (multiple lines)>
host: i586-suse-linux-gnu
build: i586-suse-linux-gnu
target: i586-suse-linux-gnu
configured with: /tmp/1/GCC332/gcc-3.3.2/configure --enable-threads=posix
--prefix=/usr --with-local-prefix=/usr/local --infodir=/usr/share/info
--mandir=/usr/share/man --libdir=/usr/lib
--enable-languages=c,c++,f77,objc,java,ada --disable-checking --enable-libgcj
--with-gxx-include-dir=/usr/include/g++ --with-slibdir=/lib --with-system-zlib
--enable-shared --enable-__cxa_atexit i586-suse-linux
(3)
>Release: 3.2.3
>Environment:
System: SunOS oberon 5.7 Generic_106541-34 sun4u sparc SUNW,UltraSPARC-IIi-Engin
e
Architecture: sun4
<machine, os, target, libraries (multiple lines)>
host: sparc-sun-solaris2.7
build: sparc-sun-solaris2.7
target: sparc-sun-solaris2.7
configured with: ../gcc-3.2.3/configure --prefix=/usr/local --enable-languages=c
,c++
Here is a small testcase:
$ cat exception.h
#ifndef _exception_h_
#define _exception_h_
class Exception {
};
#endif
$ cat libf1.cpp
#include "exception.h"
extern "C" void f1() {
throw Exception();
}
$ cat test_exception.cpp
#include <iostream>
#include <dlfcn.h>
#include "exception.h"
using namespace std;
void f0 () {
throw Exception() ;
}
main() {
try {
f0();
} catch (Exception& e) {
cerr << "f0: Exception. " << endl;
} catch (...) {
cerr << "f0: unknown exception - expected: Exception. " << endl;
}
void *lib_f1;
void (*f1_call)();
if (!(lib_f1=dlopen("./libf1.so",RTLD_LAZY))) {
cerr << endl;
cerr << "Can't open ./libf1.so." << endl;
cerr << endl;
exit(1);
}
if (!(f1_call=(void (*)())dlsym(lib_f1,"f1"))) {
cerr << endl;
cerr << "Can't bind f1." << endl;
cerr << endl;
exit(2);
}
try {
(*f1_call)();
} catch (Exception& e) {
cerr << "f1: Exception. " << endl;
} catch (...) {
cerr << "f1: unknown exception - expected: Exception. " << endl;
}
dlclose(lib_f1);
}
$ cat Makefile
CC = g++
all: test_exception libf1.so
test_exception: test_exception.cpp exception.h
$(CC) -ldl -o test_exception test_exception.cpp
libf1.so: libf1.cpp exception.h
$(CC) -fPIC -shared -Wl,-soname,libf1.so -o libf1.so libf1.cpp
#$(CC) -fPIC -G -o libf1.so libf1.cpp
clean:
rm -f *.o libf?.so core* a.out test_exception
--
Summary: exception not caught in shared lib if using dlopen
Product: gcc
Version: 3.3.2
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: frank dot schaedlich at asg dot com
CC: gcc-bugs at gcc dot gnu dot org
GCC build triplet: i586-suse-linux-gnu
GCC host triplet: i586-suse-linux-gnu
GCC target triplet: i586-suse-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17721
