GNAT CE 2019 C++ Link Failure With Mojave

GNAT CE 2019 C++ Link Failure With Mojave

[Roger]

Mac-Mini 2018
OSX 10.14.5 Mojave
GPRBUILD Community 2019 (20190517) (x86_64-apple-darwin17.7.0)
ImageMagick-7.0.8-35

The C++ code below fails to link on my Mac-Mini under Mojave:

#include <Magick++.h>
#include <iostream>
#include <string>

using namespace std;
using namespace Magick;

int main(int argc, char **argv)
  {
  string  Logo_File = "../images/logo.jpg";
  Image   logo_image;

  Magick::InitializeMagick(*argv);
  logo_image.read(Logo_File);
  return 0;
}

Failure message:
Undefined symbols for architecture x86_64:
  "Magick::Image::read(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)", referenced from:
      _main in display_logo.o
ld: symbol(s) not found for architecture x86_64
collect2: error: ld returned 1 exit status
gprbuild: link of display_logo.cpp failed
gprbuild: failed command was: /opt/gnat/2019/bin/g++ display_logo.o libshow_logo.a -L/opt/lib -lMagickCore-7.Q16HDRI -lMagick++-7.Q16HDRI -g -Wl,-rpath,/opt/lib -o /Ada_Source/OglAda_Examples/imagemagick/logo//display_logo

This code works with GNAT CE 2019 on my MacBook under High Sierra.
It also works using XCode on my Mac-Mini.
Failure occurs for both brew imagemagick and locally built imagemegick.

I use Magick::Image::read and related imagemagick routines in C++ interface code for a number of Ada projects which all build without error on my MacBook under High Sierra.

Any assistance will be greatly appreciated.
Thanks,
Roger 

Re: GNAT CE 2019 C++ Link Failure With Mojave

[Jeffrey R. Carter]

On 7/14/19 6:27 AM, Roger wrote:
> 
> I use Magick::Image::read and related imagemagick routines in C++ interface code for a number of Ada projects which all build without error on my MacBook under High Sierra.

Why not use the all-Ada Generic Image Decoder?

https://sourceforge.net/projects/gen-img-dec/

-- 
Jeff Carter
"I have a very small head and I had
better learn to live with it ..."
Edsger Dijkstra
158

Re: GNAT CE 2019 C++ Link Failure With Mojave

[Roger]

On Sunday, July 14, 2019 at 8:17:12 PM UTC+10, Jeffrey R. Carter wrote:
> On 7/14/19 6:27 AM, Roger wrote:
> > 
> > I use Magick::Image::read and related imagemagick routines in C++ interface code for a number of Ada projects which all build without error on my MacBook under High Sierra.
> 
> Why not use the all-Ada Generic Image Decoder?
> 
> https://sourceforge.net/projects/gen-img-dec/
> 
> -- 
> Jeff Carter
> "I have a very small head and I had
> better learn to live with it ..."
> Edsger Dijkstra
> 158

Thanks for the suggestion which I will investigate.
However, there are other functions of imagemagick that I use.
The code using the read function that I posted is just one example.
In any case, I would still like to know why this problem occurs.
Best regards,
Roger

Re: GNAT CE 2019 C++ Link Failure With Mojave

[Roger]

Problem solved.
The failure seems to have been caused by the C++ compiler (G++) supplied with GNAT 2019.
Changing to the llvm compiler (/usr/bin/clang++) solved the problem.