为什么会报错？是不是安卓库函数里面没有这个函数的实现呢？

Question

在做ndk的开发时，应用的自己编写的类库里面有用到rand（）srand（int）来求的随机数，但是在编译的时候报出：E:/DeveloperTools/android-ndk-r9/toolchains/x86-4.6/prebuilt/windows/bin/../lib/gcc/i686-linux-android/4.6/../../../../i686-linux-android/bin/ld.exe: E:/MagickJava/Interactive_Sale_Assistant/jni/libs/odi/libQT_ODI_linux.a(ITextureHelper.o): in function ITextureHelper::RandList(std::list<Magick::Image, std::allocator<Magick::Image> >*):ITextureHelper.cpp(.text+0xd16): error: undefined reference to 'srand'如何解决呢？望大神帮助指点。谢谢！环境：cygwin+ndk-r9;Android.mk:include $(CLEAR_VARS)  LOCAL_MODULE := Magick++  LOCAL_SRC_FILES := libs/magick/libMagick++-6.Q16.soinclude $(PREBUILT_SHARED_LIBRARY)  include $(CLEAR_VARS)  LOCAL_MODULE := MagickCore  LOCAL_SRC_FILES := libs/magick/libMagickCore-6.Q16.so  include $(PREBUILT_SHARED_LIBRARY)  include $(CLEAR_VARS)  LOCAL_MODULE := MagickWand  LOCAL_SRC_FILES := libs/magick/libMagickWand-6.Q16.soinclude $(PREBUILT_SHARED_LIBRARY)  include $(CLEAR_VARS)LOCAL_MODULE := WellShapedLOCAL_SRC_FILES := net_chinaeko_bis_isa_graphics_WellShapedToJNI.cppLOCAL_C_INCLUDES := \$(LOCAL_PATH)/include/ODI \$(LOCAL_PATH)/include/ImageMagick-6LOCAL_CFLAGS := -D__cplusplus -g -O4 -fpic \-D_STLP_USE_NEWALLOC #LOCAL_CPPFLAGS += -fexceptions -frttiLOCAL_LDFLAGS += -L$(prebuilt_stdcxx_PATH) -l gnustl_static -l supc++ LOCAL_SHARED_LIBRARIES := -l ODI_interfaceSO \-l ODI_interfaceA \-l Magick++ \-l MagickCore \-l MagickWand \LOCAL_STATIC_LIBRARIES :=\-l gnustl_static \-l supc++ LOCAL_STATIC_LIBRARIES := ./libs/odi/libQT_ODI_linux.ainclude $(BUILD_SHARED_LIBRARY)Application.mk:APP_STL := gnustl_staticAPP_SUPC := supc++APP_MODULES := libWellShapedAPP_ABI := x86APP_PLATFORM := android-9

Answer 1

undefined reference to 'srand'

srand没有定义就使用了,打开你的XXX.c或者XXX.cpp文件看看

Answer 2

把proj.android文件夹下的obj文件夹删除，重新编译试试