Question

我正在研究MacOSX 10.7.2和Xcode 4.2.1。我使用port安装了libpng，我试图在我的应用程序中加载PNG图像，但是我收到链接器错误：

Undefined symbols for architecture x86_64:
  "_png_create_read_struct", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
  "_png_create_info_struct", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
  "_png_destroy_read_struct", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
  "_png_set_longjmp_fn", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
  "_png_init_io", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
  "_png_set_sig_bytes", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
  "_png_read_png", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
  "_png_get_IHDR", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
  "_png_get_rowbytes", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
  "_png_get_rows", referenced from:
      loadPngImage(char*, int&, int&, bool&, unsigned char**) in test.o
ld: symbol(s) not found for architecture x86_64

我使用

在我的项目中加入了png.h

#include "/usr/X11/include/png.h"

我知道libpng基于zlib，因此我在“其他链接器标记”中包含了-lz但没有任何更改。

有关如何使其发挥作用的任何建议吗？

Answer 1

我解决了手动安装libpng：

从official web site

，进入下载的文件夹并启动

cp ./scripts/makefile.darwin makefile
make 
sudo make install
make clean

如果它不起作用（在我的情况下）用TextEdit（或等效的）打开makefile并更改行

ARCH="-arch i386 -arch x86_64"

in

ARCH=-arch x86_64

（假设您的系统当然是64位）。

这可能还不够。 Xcode仍无法找到该库。我解决了使用

cd /usr/local/lib
sudo ln -s libpng15.dylib ./libpng15.15.dylib

这就是诀窍。现在它工作正常。

MacOSX下与libpng的链接器错误

1 个答案: