Android NDK: Function va_start / va_end could not be resolved

问题

I trying to use va_start and va_end functions in my project, but eclipse don't want to resolve it as functions. gcc compiles whole project without errors...

[myfile.cpp]

#include <stdio.h>
#include <stdarg.h>
[...]
inline void ShowDbgMsg( const char* str, ... )
{
    va_list argptr;
    va_start(argptr, str);
    vprintf(str, argptr);
    va_end(argptr);
}
[...]

[Android.mk]

[...]
LOCAL_C_INCLUDES := jni/pvrTools/ jni/igel/ $(STLPORT_BASE)/stlport
[...]

Eclipse says:

[...]
Description Resource    Path    Location    Type
Function 'va_start' could not be resolved   igel.comdef.h   /NativeProject/jni/igel    line 195 Semantic Error
Function 'va_end' could not be resolved igel.comdef.h   /NativeProject/jni/igel  line 203   Semantic Error
Function 'va_start' could not be resolved   igel.string.h   /NativeProject/jni/igel line 341    Semantic Error
Function 'va_end' could not be resolved igel.string.h   /NativeProject/jni/igel line 351    Semantic Error
[...]

So, it looks like Eclipse unable to locate something... How to solve this issue? Thanks in advance!

P.S.> Project->Index->Rebuild didn't help. :(

回答1:

My solution is also not pretty. But after you've deleted the error markers 100 times, try putting this code somewhere before you include stdlib.h. Then define ECLIPSEBUILD=1 in Project::Properties::C++ General::Paths and Symbols.

  

    #if ECLIPSEBUILD // this part is just to fix spurious Eclipse errors
    typedef __builtin_va_list va_list;
    #define va_start(v,l)   __builtin_va_start(v,l)
    #define va_end(v)   __builtin_va_end(v)
    #define va_arg(v,l) __builtin_va_arg(v,l)
    #if !defined(__STRICT_ANSI__) || __STDC_VERSION__ + 0 >= 199900L || defined(__GXX_EXPERIMENTAL_CXX0X__)
    #define va_copy(d,s)    __builtin_va_copy(d,s)
    #endif
    #define __va_copy(d,s)  __builtin_va_copy(d,s)
    typedef __builtin_va_list __gnuc_va_list;
    typedef __gnuc_va_list va_list;
    typedef va_list __va_list;
    #endif

回答2:

I solve this issue by replacing my va_* code with embedded compiler features:

#ifdef IGEL_PLATFORM_ANDROID
#   define ShowDbgMsg(...)  ((void)__android_log_print(ANDROID_LOG_INFO, "igel-debug", __VA_ARGS__))
#else
inline void ShowDbgMsg( const char* str, ... )
{
    va_list argptr;
    va_start(argptr, str);
    vprintf(str, argptr);
    va_end(argptr);
}
#endif // IGEL_PLATFORM_ANDROID

I know it's not a good solution, but it works.

回答3:

#include <stdarg.h> // includes va_list

inline void ShowDbgMsg(char* format, ...)
{
  va_list ap;      
  va_start( ap, format );

// replace vfprintf( stderr, format, ap ) with:

   __android_log_vprint(0, __FILE__, format, ap);
  va_end( ap );
}

来源：https://stackoverflow.com/questions/11720411/android-ndk-function-va-start-va-end-could-not-be-resolved

标签

android

android-ndk