我正在尝试使用 MinGW 在 Windows 上构建一个基本的 FANN（快速人工神经网络）项目。但是，每当我尝试链接可执行文件时，都会遇到一堆undefined reference to错误。有趣的是，如果我根本不链接库，我会收到更多错误，这意味着至少有一些库正在运行。我试图编译和链接的文件的代码是：
#include "doublefann.h"
int main() {
const unsigned int num_input_neurons = 9;
const unsigned int num_output_neurons = 1;
const unsigned int num_layers = 3;
const unsigned int num_hidden_neurons = 9;
const float desired_error = (const float) 0;
const unsigned int max_epochs = 500000;
const unsigned int epochs_between_reports = 1000;
struct fann *ann = fann_create_standard(num_layers,
num_input_neurons,
num_hidden_neurons,
num_output_neurons);
fann_set_activation_function_hidden(ann, FANN_SIGMOID_SYMMETRIC);
fann_set_activation_function_output(ann, FANN_SIGMOID_SYMMETRIC);
fann_train_on_file(ann,
"titanic-training.data",
max_epochs,
epochs_between_reports,
desired_error);
fann_save(ann, "titanic.net");
fann_destroy(ann);
return 0;
}
我用来编译和链接的命令是：
gcc -Wall -Ifann\src\include titanic-train.c -Lfann\bin -lfanndouble -o titanic-train.exe
我回来的错误是：
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0x7f): undefined reference to `fann_set_activation_function_hidden'
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0x93): undefined reference to `fann_set_activation_function_output'
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0xbf): undefined reference to `fann_train_on_file'
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0xd3): undefined reference to `fann_save'
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0xdf): undefined reference to `fann_destroy'
c:/fragileprograms/mingw-native/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/ld.exe: C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o: bad reloc address 0x64 in section `.rdata'
c:/fragileprograms/mingw-native/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/ld.exe: final link failed: Invalid operation
collect2.exe: error: ld returned 1 exit status
如果我根本不链接库，我会得到：
C:\Users\kunkelwe\AppData\Local\Temp\ccyOO3jL.o:titanic-train.c:(.text+0x67): undefined reference to `fann_create_standard'
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0x7f): undefined reference to `fann_set_activation_function_hidden'
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0x93): undefined reference to `fann_set_activation_function_output'
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0xbf): undefined reference to `fann_train_on_file'
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0xd3): undefined reference to `fann_save'
C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o:titanic-train.c:(.text+0xdf): undefined reference to `fann_destroy'
c:/fragileprograms/mingw-native/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/ld.exe: C:\Users\kunkelwe\AppData\Local\Temp\ccsWQg66.o: bad reloc address 0x64 in section `.rdata'
c:/fragileprograms/mingw-native/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/ld.exe: final link failed: Invalid operation
collect2.exe: error: ld returned 1 exit status
编辑：
按照Haroogan的要求，我跑了nm fanndouble.lib。输出相当广泛，因此我没有将其全部粘贴在这里，而是通过 pastebin 在这里提供：http ://pastebin.com/raw.php?i=vybFhEcX
我不熟悉nm，但文件中似乎确实存在丢失的符号。
编辑#2：
doublefann.h 的内容为：http: //pastebin.com/mrHKJi8C
fann.h 的内容包括：http ://pastebin.com/gTrHCYAg
可以通过使用 MinGW 重新编译库来解决问题吗？
编辑＃3：
做出 Haroogan 建议的改变是有效的！除了这些更改之外，我还必须通过添加以下内容来修改 FANN 的 CMakeLists.txt 文件：
if (WIN32)
ADD_DEFINITIONS(-DFANN_DLL_EXPORTS)
endif (WIN32)
然后，运行cmake -G "MinGW Makefiles"，然后mingw32-make在项目的根目录中生成一个文件 libdoublefann.dll，当链接并包含在 .exe 的目录中时，最终允许我运行我的程序。