https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70636
Bug ID: 70636
Summary: Link failure when C++ brace initialization is used
Product: gcc
Version: 5.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: steveire at gmail dot com
Target Milestone: ---
$ g++ --version
g++ (Ubuntu 5.2.1-22ubuntu2) 5.2.1 20151010
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
$ cat brace-init.cpp
#include <vector>
#include <string>
class Expression
{
public:
std::vector<int> args;
};
Expression getExpr(const Expression& def = {})
{
return def;
}
int main()
{
auto a = getExpr();
// auto a = getExpr({});
}
$ g++ brace-init.cpp -std=c++11 -v
Using built-in specs.
COLLECT_GCC=/usr/bin/g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/5/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 5.2.1-22ubuntu2'
--with-bugurl=file:///usr/share/doc/gcc-5/README.Bugs
--enable-languages=c,ada,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr
--program-suffix=-5 --enable-shared --enable-linker-build-id
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes
--with-default-libstdcxx-abi=new --enable-gnu-unique-object
--disable-vtable-verify --enable-libmpx --enable-plugin --with-system-zlib
--disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo
--with-java-home=/usr/lib/jvm/java-1.5.0-gcj-5-amd64/jre --enable-java-home
--with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-5-amd64
--with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-5-amd64
--with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar
--enable-objc-gc --enable-multiarch --disable-werror --with-arch-32=i686
--with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib
--with-tune=generic --enable-checking=release --build=x86_64-linux-gnu
--host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 5.2.1 20151010 (Ubuntu 5.2.1-22ubuntu2)
COLLECT_GCC_OPTIONS='-std=c++11' '-v' '-shared-libgcc' '-mtune=generic'
'-march=x86-64'
/usr/lib/gcc/x86_64-linux-gnu/5/cc1plus -quiet -v -imultiarch x86_64-linux-gnu
-D_GNU_SOURCE brace-init.cpp -quiet -dumpbase brace-init.cpp -mtune=generic
-march=x86-64 -auxbase brace-init -std=c++11 -version -fstack-protector-strong
-Wformat -Wformat-security -o /tmp/ccsM0fgs.s
GNU C++11 (Ubuntu 5.2.1-22ubuntu2) version 5.2.1 20151010 (x86_64-linux-gnu)
compiled by GNU C version 5.2.1 20151010, GMP version 6.0.0, MPFR
version 3.1.3, MPC version 1.0.3
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
ignoring duplicate directory "/usr/include/x86_64-linux-gnu/c++/5"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring nonexistent directory
"/usr/lib/gcc/x86_64-linux-gnu/5/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
/usr/include/c++/5
/usr/include/x86_64-linux-gnu/c++/5
/usr/include/c++/5/backward
/usr/lib/gcc/x86_64-linux-gnu/5/include
/usr/local/include
/usr/lib/gcc/x86_64-linux-gnu/5/include-fixed
/usr/include/x86_64-linux-gnu
/usr/include
End of search list.
GNU C++11 (Ubuntu 5.2.1-22ubuntu2) version 5.2.1 20151010 (x86_64-linux-gnu)
compiled by GNU C version 5.2.1 20151010, GMP version 6.0.0, MPFR
version 3.1.3, MPC version 1.0.3
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 5ed623d6fe11f4bcc1afee70f77e33b0
COLLECT_GCC_OPTIONS='-std=c++11' '-v' '-shared-libgcc' '-mtune=generic'
'-march=x86-64'
as -v --64 -o /tmp/cc7GSdPa.o /tmp/ccsM0fgs.s
GNU assembler version 2.25.1 (x86_64-linux-gnu) using BFD version (GNU Binutils
for Ubuntu) 2.25.1
COMPILER_PATH=/usr/lib/gcc/x86_64-linux-gnu/5/:/usr/lib/gcc/x86_64-linux-gnu/5/:/usr/lib/gcc/x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/5/:/usr/lib/gcc/x86_64-linux-gnu/
LIBRARY_PATH=/usr/lib/gcc/x86_64-linux-gnu/5/:/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/5/../../../../lib/:/lib/x86_64-linux-gnu/:/lib/../lib/:/usr/lib/x86_64-linux-gnu/:/usr/lib/../lib/:/usr/lib/gcc/x86_64-linux-gnu/5/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-std=c++11' '-v' '-shared-libgcc' '-mtune=generic'
'-march=x86-64'
/usr/lib/gcc/x86_64-linux-gnu/5/collect2 -plugin
/usr/lib/gcc/x86_64-linux-gnu/5/liblto_plugin.so
-plugin-opt=/usr/lib/gcc/x86_64-linux-gnu/5/lto-wrapper
-plugin-opt=-fresolution=/tmp/ccq481oT.res -plugin-opt=-pass-through=-lgcc_s
-plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lc
-plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lgcc --sysroot=/
--build-id --eh-frame-hdr -m elf_x86_64 --hash-style=gnu --as-needed
-dynamic-linker /lib64/ld-linux-x86-64.so.2 -z relro
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/crt1.o
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/crti.o
/usr/lib/gcc/x86_64-linux-gnu/5/crtbegin.o -L/usr/lib/gcc/x86_64-linux-gnu/5
-L/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu
-L/usr/lib/gcc/x86_64-linux-gnu/5/../../../../lib -L/lib/x86_64-linux-gnu
-L/lib/../lib -L/usr/lib/x86_64-linux-gnu -L/usr/lib/../lib
-L/usr/lib/gcc/x86_64-linux-gnu/5/../../.. /tmp/cc7GSdPa.o -lstdc++ -lm -lgcc_s
-lgcc -lc -lgcc_s -lgcc /usr/lib/gcc/x86_64-linux-gnu/5/crtend.o
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/crtn.o
/tmp/cc7GSdPa.o: In function `main':
brace-init.cpp:(.text+0x49): undefined reference to `std::vector<int,
std::allocator<int> >::vector()'
collect2: error: ld returned 1 exit status
