https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63550
Bug ID: 63550
Summary: Multiple definition errors occur only with -fgnu-tm
Product: gcc
Version: 5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: spear at cse dot lehigh.edu
Templates instantiated within transactions from multiple files result in
multiple-definition errors at link time. Errors do not occur when compiling
without TM, or when all source files are concatenated. Should these symbols be
emitted as weak?
The smallest testcase entails two files, each of which instantiates
std::vector<int> and uses the initializer list constructor. #define is used to
show behavior with and without instantiation from within a transaction.
f1.cc:
#include <vector>
#ifdef USE_TM
#define TX __transaction_atomic
#else
#define TX
#endif
std::vector<int>* v1;
void test1() {
TX {
// make a vector with some elements in it
v1 = new std::vector<int>({1, 2, 3, 4, 5});
}
}
int main(int argc, char** argv) { }
f2.cc:
#include <vector>
#ifdef USE_TM
#define TX __transaction_atomic
#else
#define TX
#endif
std::vector<int>* v2;
void test2() {
TX {
v2 = new std::vector<int>({11, 13, 15, 17});
}
}
The following script builds the two files four ways: with and without
instantation of std::vector<int>({...}) within a transaction; and with and
without multiple .cc files.
build.sh:
echo "Building from 2 files, no TM"
g++ f1.cc f2.cc -std=c++11 -fgnu-tm -o no_tm_2_file.exe
echo "Building from 2 files, TM"
g++ -DUSE_TM f1.cc f2.cc -std=c++11 -fgnu-tm -o yes_tm_2_file.exe
echo "Building from 1 file, no TM"
cat f1.cc f2.cc > f.cc; g++ f.cc -std=c++11 -fgnu-tm -o no_tm_1_file.exe; rm
f.cc
echo "Building from 1 file, TM"
cat f1.cc f2.cc > f.cc; g++ -DUSE_TM f.cc -std=c++11 -fgnu-tm -o
yes_tm_1_file.exe; rm f.cc
Link errors occur only in one case. Other three cases produce executables:
Output:
sh build.sh
Building from 2 files, no TM
Building from 2 files, TM
/tmp/cchUc9zn.o: In function `transaction clone for std::vector<int,
std::allocator<int> >::vector(std::initializer_list<int>, std::allocator<int>
const&)':
f2.cc:(.text+0x1b4): multiple definition of `transaction clone for
std::vector<int, std::allocator<int> >::vector(std::initializer_list<int>,
std::allocator<int> const&)'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x1c6): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for
std::allocator<int>::allocator() [clone .localalias.31]':
f2.cc:(.text+0x180): multiple definition of `transaction clone for
std::allocator<int>::allocator()'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x192): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for
std::allocator<int>::~allocator() [clone .localalias.30]':
f2.cc:(.text+0x19a): multiple definition of `transaction clone for
std::allocator<int>::~allocator()'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x1ac): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for
__gnu_cxx::new_allocator<int>::new_allocator() [clone .localalias.29]':
f2.cc:(.text+0x24a): multiple definition of `transaction clone for
__gnu_cxx::new_allocator<int>::new_allocator()'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x25c): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for
__gnu_cxx::new_allocator<int>::~new_allocator() [clone .localalias.28]':
f2.cc:(.text+0x254): multiple definition of `transaction clone for
__gnu_cxx::new_allocator<int>::~new_allocator()'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x266): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for std::_Vector_base<int,
std::allocator<int> >::_Vector_base(std::allocator<int> const&) [clone
.localalias.27]':
f2.cc:(.text+0x25e): multiple definition of `transaction clone for
std::_Vector_base<int, std::allocator<int> >::_Vector_base(std::allocator<int>
const&)'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x270): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for std::_Vector_base<int,
std::allocator<int> >::~_Vector_base() [clone .localalias.23]':
f2.cc:(.text+0x3a4): multiple definition of `transaction clone for
std::_Vector_base<int, std::allocator<int> >::~_Vector_base()'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x3b6): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for std::_Vector_base<int,
std::allocator<int> >::_Vector_impl::_Vector_impl(std::allocator<int> const&)
[clone .localalias.22]':
f2.cc:(.text+0x412): multiple definition of `transaction clone for
std::_Vector_base<int, std::allocator<int>
>::_Vector_impl::_Vector_impl(std::allocator<int> const&)'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x424): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for std::_Vector_base<int,
std::allocator<int> >::_Vector_impl::~_Vector_impl() [clone .localalias.15]':
f2.cc:(.text+0x58c): multiple definition of `transaction clone for
std::_Vector_base<int, std::allocator<int> >::_Vector_impl::~_Vector_impl()'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x59e): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for
std::allocator<int>::allocator(std::allocator<int> const&) [clone
.localalias.14]':
f2.cc:(.text+0x5a6): multiple definition of `transaction clone for
std::allocator<int>::allocator(std::allocator<int> const&)'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x5b8): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for
__gnu_cxx::new_allocator<int>::new_allocator(__gnu_cxx::new_allocator<int>
const&) [clone .localalias.8]':
f2.cc:(.text+0x67e): multiple definition of `transaction clone for
__gnu_cxx::new_allocator<int>::new_allocator(__gnu_cxx::new_allocator<int>
const&)'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x690): first defined here
/tmp/cchUc9zn.o: In function `transaction clone for void std::_Construct<int,
int const&>(int*, int const&) [clone .localalias.2]':
f2.cc:(.text+0x772): multiple definition of `transaction clone for void
std::_Construct<int, int const&>(int*, int const&)'
/tmp/ccvjPFgv.o:f1.cc:(.text+0x784): first defined here
collect2: error: ld returned 1 exit status
Building from 1 file, no TM
Building from 1 file, TM
