• TheGag96 (11/11) Apr 16 2015 Hi, I've got this project that requires me to link into a C++
• FreeSlave (3/15) Apr 16 2015 Can't get to linux machine now, but you can try place -L-lstdc++
• John Colvin (6/18) Apr 16 2015 I don't know why that's happening, but you can explicitly link
• TheGag96 (9/33) Apr 16 2015 I had wanted to try this too, but I wasn't sure if the linker
• Dicebot (6/18) Apr 16 2015 Simple issue but unpleasant fix. You always must use C++ library
• Jacob Carlborg (4/9) Apr 16 2015 The title says (Linux), where DMD uses GCC and not DMC.
• Dicebot (3/14) Apr 17 2015 Does DMD also use GCC conventions on Linux when compiling
• Jacob Carlborg (8/10) Apr 17 2015 Not exactly sure that you mean by "conventions" but "extern(C++)" and
• Steven Schveighoffer (7/17) Apr 16 2015 Try dmd -v to tell you exactly what command it is running for link. Then...
• TheGag96 (6/16) Apr 16 2015 Got it!! This is what helped me the most. I compiled a regular

"TheGag96" <thegag96 gmail.com> writes:

Hi, I've got this project that requires me to link into a C++
backend. It works just fine when using GDC:

gdc *.d [client libraries]

However, this command using DMD does not work:

dmd -L-lstdc++ *.d [client libraries]

I still get errors involving the standard library not being added
like:

/usr/include/c++/4.8/iostream:74: undefine reference to
`std::ios_base::Init::Init()'
(etc.)

What do I need to do to make this work? Thanks.

"FreeSlave" <freeslave93 gmail.com> writes:

On Thursday, 16 April 2015 at 08:51:15 UTC, TheGag96 wrote:
 Hi, I've got this project that requires me to link into a C++
 backend. It works just fine when using GDC:

 gdc *.d [client libraries]

 However, this command using DMD does not work:

 dmd -L-lstdc++ *.d [client libraries]

 I still get errors involving the standard library not being 
 added
 like:

 /usr/include/c++/4.8/iostream:74: undefine reference to
 `std::ios_base::Init::Init()'
 (etc.)

 What do I need to do to make this work? Thanks.

Can't get to linux machine now, but you can try place -L-lstdc++
after source files.

"John Colvin" <john.loughran.colvin gmail.com> writes:

On Thursday, 16 April 2015 at 08:51:15 UTC, TheGag96 wrote:
 Hi, I've got this project that requires me to link into a C++
 backend. It works just fine when using GDC:

 gdc *.d [client libraries]

 However, this command using DMD does not work:

 dmd -L-lstdc++ *.d [client libraries]

 I still get errors involving the standard library not being 
 added
 like:

 /usr/include/c++/4.8/iostream:74: undefine reference to
 `std::ios_base::Init::Init()'
 (etc.)

 What do I need to do to make this work? Thanks.

I don't know why that's happening, but you can explicitly link 
using gcc (or ld/gold directly) if you need to. E.g.

dmd -c myFile.d
gcc myFile.o -lphobos2

or whatever is necessary on your project/system.

"TheGag96" <thegag96 gmail.com> writes:

On Thursday, 16 April 2015 at 09:46:40 UTC, John Colvin wrote:
 On Thursday, 16 April 2015 at 08:51:15 UTC, TheGag96 wrote:
 Hi, I've got this project that requires me to link into a C++
 backend. It works just fine when using GDC:

 gdc *.d [client libraries]

 However, this command using DMD does not work:

 dmd -L-lstdc++ *.d [client libraries]

 I still get errors involving the standard library not being 
 added
 like:

 /usr/include/c++/4.8/iostream:74: undefine reference to
 `std::ios_base::Init::Init()'
 (etc.)

 What do I need to do to make this work? Thanks.

 I don't know why that's happening, but you can explicitly link 
 using gcc (or ld/gold directly) if you need to. E.g.

 dmd -c myFile.d
 gcc myFile.o -lphobos2

 or whatever is necessary on your project/system.

I had wanted to try this too, but I wasn't sure if the linker 
knew where phobos2 was on my system. I just tried this now for 
funsies:

dmd -c *.d
g++ main.o [client files] -lphobos2

With or without that -lphobos2 flag, I get errors like these:

main.d(.text._Dmain+0x18e): undefined reference to 
`D3std5stdio16__T7writeln(TAyaZ7writeFAyaZv'

"Dicebot" <public dicebot.lv> writes:

On Thursday, 16 April 2015 at 08:51:15 UTC, TheGag96 wrote:
 Hi, I've got this project that requires me to link into a C++
 backend. It works just fine when using GDC:

 gdc *.d [client libraries]

 However, this command using DMD does not work:

 dmd -L-lstdc++ *.d [client libraries]

 I still get errors involving the standard library not being 
 added
 like:

 /usr/include/c++/4.8/iostream:74: undefine reference to
 `std::ios_base::Init::Init()'
 (etc.)

 What do I need to do to make this work? Thanks.

Simple issue but unpleasant fix. You always must use C++ library 
that matches base C++ compiler. For GDC it is GCC (which is used 
by default). For DMD it is DMC (Digital Mars C compiler). For LDC 
it is whatever Clang standard library is called. All those are 
incompatible because rely on different compiler built-ins.

Jacob Carlborg <doob me.com> writes:

On 2015-04-16 11:56, Dicebot wrote:

 Simple issue but unpleasant fix. You always must use C++ library that
 matches base C++ compiler. For GDC it is GCC (which is used by default).
 For DMD it is DMC (Digital Mars C compiler). For LDC it is whatever
 Clang standard library is called. All those are incompatible because
 rely on different compiler built-ins.

The title says (Linux), where DMD uses GCC and not DMC.

-- 
/Jacob Carlborg

"Dicebot" <public dicebot.lv> writes:

On Thursday, 16 April 2015 at 12:39:07 UTC, Jacob Carlborg wrote:
 On 2015-04-16 11:56, Dicebot wrote:

 Simple issue but unpleasant fix. You always must use C++ 
 library that
 matches base C++ compiler. For GDC it is GCC (which is used by 
 default).
 For DMD it is DMC (Digital Mars C compiler). For LDC it is 
 whatever
 Clang standard library is called. All those are incompatible 
 because
 rely on different compiler built-ins.

 The title says (Linux), where DMD uses GCC and not DMC.

Does DMD also use GCC conventions on Linux when compiling 
extern(C++) code? I didn't know that.

Jacob Carlborg <doob me.com> writes:

On 2015-04-17 10:16, Dicebot wrote:

 Does DMD also use GCC conventions on Linux when compiling extern(C++)
 code? I didn't know that.

Not exactly sure that you mean by "conventions" but "extern(C++)" and 
"extern(C)" follows the ABI of the system compiler. On Linux that is 
GCC, on OS X it's Clang/GCC, on Windows it's either DMC or VS depending 
on what object format is used, I guess.

DMC is not even available for any other platform than Windows.

-- 
/Jacob Carlborg

Steven Schveighoffer <schveiguy yahoo.com> writes:

On 4/16/15 4:51 AM, TheGag96 wrote:
 Hi, I've got this project that requires me to link into a C++
 backend. It works just fine when using GDC:

 gdc *.d [client libraries]

 However, this command using DMD does not work:

 dmd -L-lstdc++ *.d [client libraries]

 I still get errors involving the standard library not being added
 like:

 /usr/include/c++/4.8/iostream:74: undefine reference to
 `std::ios_base::Init::Init()'
 (etc.)

Try dmd -v to tell you exactly what command it is running for link. Then 
play around with the link line to see if you can figure out a way to 
link it correctly.

We can work on fixing the situation from there. Maybe there's a way to 
link using dmd, maybe we have to fix dmd so it allows the correct link call.

-Steve

"TheGag96" <thegag96 gmail.com> writes:

On Thursday, 16 April 2015 at 12:57:12 UTC, Steven Schveighoffer 
wrote:
 /usr/include/c++/4.8/iostream:74: undefine reference to
 `std::ios_base::Init::Init()'
 (etc.)

 Try dmd -v to tell you exactly what command it is running for 
 link. Then play around with the link line to see if you can 
 figure out a way to link it correctly.

 We can work on fixing the situation from there. Maybe there's a 
 way to link using dmd, maybe we have to fix dmd so it allows 
 the correct link call.

 -Steve

Got it!! This is what helped me the most. I compiled a regular 
C++ program with the -v flag, found where my libstdc++.a was, 
added it to the command and bam. I really should have thought of 
this one earlier... Thanks for the quick support, everyone!