Linux OpenCV 静态链接错误

错误一：

undefined reference to `dlopen'

undefined reference to `dlerror'

undefined reference to `dlsym'

对dlopen, dlerror, dlsym 未定义的引用， 缺少链接库， 链接时加上选项 -ldl

参考:

1. http://blog.csdn.net/houjixin/article/details/8624581
2. http://stackoverflow.com/questions/29557683/undefined-reference-to-symbol-dlsymglibc-2-4

错误二：

对icvPuts, icvGets 未定义的引用，编译错误如下：

./obj/local/armeabi-v7a/libopencv_core.a(persistence.cpp.o): In function `icvPuts(CvFileStorage*, char const*)':
persistence.cpp:(.text._ZL7icvPutsP13CvFileStoragePKc+0x20): undefined reference to `gzputs'
./obj/local/armeabi-v7a/libopencv_core.a(persistence.cpp.o): In function `icvGets(CvFileStorage*, char*, int)':
persistence.cpp:(.text._ZL7icvGetsP13CvFileStoragePci+0x26): undefined reference to `gzgets'
./obj/local/armeabi-v7a/libopencv_core.a(persistence.cpp.o): In function `icvXMLSkipSpaces(CvFileStorage*, char*, int)':
persistence.cpp:(.text._ZL16icvXMLSkipSpacesP13CvFileStoragePci+0x1e2): undefined reference to `gzgets'
persistence.cpp:(.text._ZL16icvXMLSkipSpacesP13CvFileStoragePci+0x208): undefined reference to `gzeof'
persistence.cpp:(.text._ZL16icvXMLSkipSpacesP13CvFileStoragePci+0x33c): undefined reference to `gzeof'
./obj/local/armeabi-v7a/libopencv_core.a(persistence.cpp.o): In function `_ZL16icvYMLSkipSpacesP13CvFileStoragePcii.clone.3':
persistence.cpp:(.text._ZL16icvYMLSkipSpacesP13CvFileStoragePcii.clone.3+0x124): undefined reference to `gzgets'
persistence.cpp:(.text._ZL16icvYMLSkipSpacesP13CvFileStoragePcii.clone.3+0x170): undefined reference to `gzeof'
/cygdrive/d/soft/NVPACK/android-ndk-r7c/build/core/build-binary.mk:366: recipe for target `obj/local/armeabi-v7a/libnative-activity.so' failed
persistence.cpp:(.text._ZL16icvYMLSkipSpacesP13CvFileStoragePcii.clone.3+0x28e): undefined reference to `gzeof'
./obj/local/armeabi-v7a/libopencv_core.a(persistence.cpp.o): In function `cvReleaseFileStorage':
persistence.cpp:(.text.cvReleaseFileStorage+0x24): undefined reference to `gzclose'
./obj/local/armeabi-v7a/libopencv_core.a(persistence.cpp.o): In function `cvOpenFileStorage':
persistence.cpp:(.text.cvOpenFileStorage+0x66e): undefined reference to `gzopen'
persistence.cpp:(.text.cvOpenFileStorage+0x8fc): undefined reference to `gzclose'
persistence.cpp:(.text.cvOpenFileStorage+0xaea): undefined reference to `gzrewind'
persistence.cpp:(.text.cvOpenFileStorage+0xbee): undefined reference to `gzrewind'
persistence.cpp:(.text.cvOpenFileStorage+0xc0a): undefined reference to `gzclose'
collect2: ld returned 1 exit status

缺少zlib库引起的， 编译链接时加上 -lz

参考：

1. http://stackoverflow.com/questions/10858055/opencv2-4-with-android-native-activity

总结： 类似的未定义的引用错误，应该都是由于缺少库的原因引起的， 静态链接OpenCV库的时候， 不仅需要链接libopencv_***.a, 也需要 dl, zlib 等库， 出现类似错误时， 直接Google 未定义引用的函数对应的库， 然后在链接中添加上.