http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47544
Summary: c++0x linker does not find =default constructor for
explicitly instantiated template
Product: gcc
Version: 4.5.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: tspit...@ieee.org
When compiling the file a.cpp below, the linker does not find the constructor
of an explicitly instantiated template if the constructor is defined using =
default.
$ cat a.cpp
template <typename T>
struct s {
s();
};
extern template struct s<int>;
template <typename T>
s<T>::s() = default;
//s<T>::s() {} // gives no error
template struct s<int>;
int main()
{
s<int> a;
}
$ g++-4.5 -std=c++0x a.cpp
/tmp/cc4PTe2q.o(.text+0x10): In function `main':
: undefined reference to `s<int>::s()'
collect2: ld returned 1 exit status
$ g++-4.5 -v
Using built-in specs.
COLLECT_GCC=g++-4.5
COLLECT_LTO_WRAPPER=/home/eeyts/root/libexec/gcc/x86_64-unknown-linux-gnu/4.5.2/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-4.5.2/configure --prefix=/home/eeyts/root
--disable-shared --enable-threads=posix --enable-__cxa_atexit --enable-libgomp
--disable-libunwind-exceptions --enable-languages=c,c++,ada
--with-gmp=/home/eeyts/root --with-mpfr=/home/eeyts/root
--with-mpc=/home/eeyts/root --with-host-libstdcxx=/usr/lib64/libstdc++.so.6
--with-ppl=/home/eeyts/root --with-cloog=/home/eeyts/root
--with-libelf=/home/eeyts/root --program-suffix=-4.5
Thread model: posix
gcc version 4.5.2 (GCC)
$ ld -v
GNU ld version 2.15.92.0.2 20040927
