编译器找不到 jpeg 和 png 库

【问题标题】：Compiler not finding jpeg and png libraries编译器找不到 jpeg 和 png 库
【发布时间】：2020-12-26 08:09:07
【问题描述】：

我已经下载并安装了这个用于绘图和可视化的 C++ 包https://github.com/alandefreitas/matplotplusplus。我已经在我的 CMake 文件中将其链接到它，并且在包含 #include <matplot/matplot.h> 时没有链接错误。但是，每当我使用库 matplot.h 中的任何函数时，我都会在编译时收到以下错误。

/usr/bin/ld: /usr/local/lib/libmatplot.a(common.cpp.o): in function `cimg_library::CImg<unsigned char>::_cimg_jpeg_error_exit(jpeg_common_struct*)':
common.cpp:(.text._ZN12cimg_library4CImgIhE21_cimg_jpeg_error_exitEP18jpeg_common_struct[_ZN12cimg_library4CImgIhE21_cimg_jpeg_error_exitEP18jpeg_common_struct]+0x1e): undefined reference to `jpeg_destroy'
/usr/bin/ld: /usr/local/lib/libmatplot.a(common.cpp.o): in function `cimg_library::CImg<unsigned char>::_save_jpeg(_IO_FILE*, char const*, unsigned int) const':
common.cpp:(.text._ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj]+0x12b): undefined reference to `jpeg_std_error'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj]+0x152): undefined reference to `jpeg_CreateCompress'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj]+0x16d): undefined reference to `jpeg_stdio_dest'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj]+0x198): undefined reference to `jpeg_set_defaults'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj]+0x1b2): undefined reference to `jpeg_set_quality'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj]+0x1c6): undefined reference to `jpeg_start_compress'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj]+0x2cf): undefined reference to `jpeg_write_scanlines'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj]+0x2ed): undefined reference to `jpeg_finish_compress'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE10_save_jpegEP8_IO_FILEPKcj]+0x302): undefined reference to `jpeg_destroy_compress'
/usr/bin/ld: /usr/local/lib/libmatplot.a(common.cpp.o): in function `cimg_library::CImg<unsigned char>::_save_png(_IO_FILE*, char const*, unsigned int) const':
common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0x2f4): undefined reference to `png_create_write_struct'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0x309): undefined reference to `png_create_info_struct'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0x32b): undefined reference to `png_set_longjmp_fn'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0x34f): undefined reference to `png_destroy_write_struct'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0x409): undefined reference to `png_init_io'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0x474): undefined reference to `png_set_IHDR'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0x485): undefined reference to `png_write_info'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0xc36): undefined reference to `png_write_image'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0xc43): undefined reference to `png_write_end'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0xc50): undefined reference to `png_destroy_write_struct'
/usr/bin/ld: common.cpp:(.text._ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj[_ZNK12cimg_library4CImgIhE9_save_pngEP8_IO_FILEPKcj]+0x1830): undefined reference to `png_destroy_write_struct'
/usr/bin/ld: /usr/local/lib/libmatplot.a(common.cpp.o): in function `cimg_library::CImg<unsigned char>::save_cimg(char const*, bool) const':
common.cpp:(.text._ZNK12cimg_library4CImgIhE9save_cimgEPKcb[_ZNK12cimg_library4CImgIhE9save_cimgEPKcb]+0x3bb): undefined reference to `compress'
/usr/bin/ld: /usr/local/lib/libmatplot.a(common.cpp.o): in function `cimg_library::CImg<unsigned char>::_load_png(_IO_FILE*, char const*, unsigned int*)':
common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x88): undefined reference to `png_sig_cmp'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0xa2): undefined reference to `png_create_read_struct'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0xb7): undefined reference to `png_create_info_struct'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0xcd): undefined reference to `png_create_info_struct'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0xef): undefined reference to `png_set_longjmp_fn'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x14a): undefined reference to `png_destroy_read_struct'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x1c9): undefined reference to `png_init_io'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x1d7): undefined reference to `png_set_sig_bytes'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x1e4): undefined reference to `png_read_info'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x20e): undefined reference to `png_get_IHDR'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x252): undefined reference to `png_get_valid'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x280): undefined reference to `png_set_filler'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x28d): undefined reference to `png_read_update_info'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x2c2): undefined reference to `png_destroy_read_struct'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x369): undefined reference to `png_set_expand_gray_1_2_4_to_8'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x389): undefined reference to `png_set_gray_to_rgb'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x3a9): undefined reference to `png_set_tRNS_to_alpha'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x41f): undefined reference to `png_read_image'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x42c): undefined reference to `png_read_end'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x461): undefined reference to `png_destroy_read_struct'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x4f1): undefined reference to `png_set_palette_to_rgb'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x683): undefined reference to `png_destroy_read_struct'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x84a): undefined reference to `png_destroy_read_struct'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj[_ZN12cimg_library4CImgIhE9_load_pngEP8_IO_FILEPKcPj]+0x9d3): undefined reference to `png_destroy_read_struct'
/usr/bin/ld: /usr/local/lib/libmatplot.a(common.cpp.o): in function `cimg_library::CImgList<unsigned char>::_load_cimg(_IO_FILE*, char const*)':
common.cpp:(.text._ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc[_ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc]+0x404): undefined reference to `uncompress'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc[_ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc]+0x70c): undefined reference to `uncompress'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc[_ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc]+0x93b): undefined reference to `uncompress'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc[_ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc]+0xce5): undefined reference to `uncompress'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc[_ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc]+0x10f7): undefined reference to `uncompress'
/usr/bin/ld: /usr/local/lib/libmatplot.a(common.cpp.o):common.cpp:(.text._ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc[_ZN12cimg_library8CImgListIhE10_load_cimgEP8_IO_FILEPKc]+0x1506): more undefined references to `uncompress' follow
/usr/bin/ld: /usr/local/lib/libmatplot.a(common.cpp.o): in function `cimg_library::CImg<unsigned char>::_load_jpeg(_IO_FILE*, char const*)':
common.cpp:(.text._ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc[_ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc]+0x67): undefined reference to `jpeg_std_error'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc[_ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc]+0xb3): undefined reference to `jpeg_CreateDecompress'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc[_ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc]+0xc5): undefined reference to `jpeg_stdio_src'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc[_ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc]+0xd2): undefined reference to `jpeg_read_header'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc[_ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc]+0xda): undefined reference to `jpeg_start_decompress'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc[_ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc]+0x1f8): undefined reference to `jpeg_read_scanlines'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc[_ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc]+0x278): undefined reference to `jpeg_finish_decompress'
/usr/bin/ld: common.cpp:(.text._ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc[_ZN12cimg_library4CImgIhE10_load_jpegEP8_IO_FILEPKc]+0x284): undefined reference to `jpeg_destroy_decompress'
/usr/bin/ld: /usr/local/lib/libmatplot.a(network.cpp.o): in function `matplot::network::process_force_layout()':
network.cpp:(.text+0x304e): undefined reference to `nodesoup::size_radiuses(std::vector<std::vector<unsigned long, std::allocator<unsigned long> >, std::allocator<std::vector<unsigned long, std::allocator<unsigned long> > > > const&, double, double)'
/usr/bin/ld: network.cpp:(.text+0x312a): undefined reference to `nodesoup::fruchterman_reingold(std::vector<std::vector<unsigned long, std::allocator<unsigned long> >, std::allocator<std::vector<unsigned long, std::allocator<unsigned long> > > > const&, unsigned int, unsigned int, unsigned int, double, std::function<void (std::vector<nodesoup::Point2D, std::allocator<nodesoup::Point2D> > const&, int)>)'
/usr/bin/ld: /usr/local/lib/libmatplot.a(network.cpp.o): in function `matplot::network::process_kawai_layout()':
network.cpp:(.text+0x3842): undefined reference to `nodesoup::size_radiuses(std::vector<std::vector<unsigned long, std::allocator<unsigned long> >, std::allocator<std::vector<unsigned long, std::allocator<unsigned long> > > > const&, double, double)'
/usr/bin/ld: network.cpp:(.text+0x390c): undefined reference to `nodesoup::kamada_kawai(std::vector<std::vector<unsigned long, std::allocator<unsigned long> >, std::allocator<std::vector<unsigned long, std::allocator<unsigned long> > > > const&, unsigned int, unsigned int, double, double)'
collect2: error: ld returned 1 exit status
make[2]: *** [CMakeFiles/example.dir/build.make:84: example] Error 1
make[1]: *** [CMakeFiles/Makefile2:76: CMakeFiles/example.dir/all] Error 2
make: *** [Makefile:84: all] Error 2

错误很多，但除了undefined reference to 'uncompress' 之外，它们都是undefined reference to png_... 或undefined reference to jpeg_... 的形式。似乎 CMake 没有找到 png 和 jpeg。我确实安装了 libjpeg 和 libpng。为什么会出现这些错误？我是否需要在我的 CMakeLists.txt 中添加行来查找 jpeg 和 png？我正在运行 Ubuntu 20.04、g++ 9.3.0 和 cmake 3.16.3。

这是一个非常简单的示例，它会产生错误。这是cmake文件

cmake_minimum_required(VERSION 3.10)

project(example)

set(CMAKE_CXX_COMPILER "c++")

find_package(Matplot++)
add_executable(example example.cpp)
target_link_libraries(example PUBLIC matplot)

这是一个示例 c++ 代码（直接从链接站点上的示例中提取）。

#include <cmath>
#include <matplot/matplot.h>

int main() {
    using namespace matplot;

    std::vector<double> x = linspace(0, 10, 150);
    std::vector<double> y = transform(x, [](auto x) { return cos(5 * x); });
    plot(x, y)->color({0, 0.7, 0.9});
    title("2-D Line Plot");
    xlabel("x");
    ylabel("cos(5x)");

    show();
    return 0;
}

【问题讨论】：

  • 这能回答你的问题吗？ What is an undefined reference/unresolved external symbol error and how do I fix it?
  • @drescherjm 我能做到，给我一分钟。
  • 至于否决票和关闭建议，我假设是你@SM，虽然那个链接的问题很有帮助，但它比这更普遍，不容易适用。我的问题要具体得多。
  • @drescherjm，有一个简单的例子。还有什么我应该包括的细节吗？
  • 我的建议是使用 CMake 重新配置 matplot 并启用 BUILD_SHARED_LIBS 选项并将 matplot 重建为共享库。我认为这可以解决这个问题。除非您在过去 4 天内没有从源更新。我在上一条评论中发布的静态库链接问题的修复是 4 天前。

标签： c++ linux cmake g++ jpeg


【解决方案1】：

我遇到了同样的问题（使用 Windows MinGW）。感谢@drescherjm 提示（添加选项-DBUILD_SHARED_LIBS=ON），这些是我用来解决问题的步骤：

git clone http://github.com/alandefreitas/matplotplusplus
cd matplotplusplus/
mkdir compil-release && cd compil-release 
rm CMakeCache.txt # if already exists
cmake .. -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=ON -DBUILD_EXAMPLES=OFF -DBUILD_TESTS=OFF -DCMAKE_INSTALL_PREFIX="${YOUR_LIB_PATH}/matplot1.0.1" 
make -j4 && make install

然后，我猜这是一个错误，我不得不手动将 .dll 复制到安装路径

cp source/matplot/libmatplot.dll ${YOUR_LIB_PATH}/matplot1.0.1/lib/

希望这对你有用。

【讨论】：

  • 我最终只保留了 matplotplusplus 文件夹作为子目录，它运行良好，但我会尝试安装会更好，谢谢。
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