交叉编译libiconv库问题（android 9系统）

下面的函数一直失败

int32_t ConvertDecode(
		const char *from_charset,
		const char *to_charset,
		const char *inbuf,
		int32_t inlen,
		char *outbuf,
		int32_t outlen)
{

	   iconv_t cd;
	   char **pin = const_cast<char**>(&inbuf);
	   char **pout = static_cast<char**>(&outbuf);
	   int32_t result = -1;

	   cd = iconv_open(to_charset,from_charset);
	   if (cd  != (reinterpret_cast<iconv_t>(-1)) )
	   {
		   if ( (iconv(cd,pin,reinterpret_cast<size_t*>(&inlen),pout,reinterpret_cast<size_t*>(&outlen) ))
			   != (static_cast<size_t>(-1)) )
		   {
			   result = 0 ;
		   }
		   iconv_close(cd);
	   }
	   return result;


}

测试发现使用android 4.4的交叉编译器编译出来的程序是没有问题，但是使用android 9的交叉编译器（ndk r20b制作的）编译出来的程序一直有问题。
后来发现是iconv函数一直失败：if ( (iconv(cd,pin,reinterpret_cast<size_t*>(&inlen),pout,reinterpret_cast<size_t*>(&outlen) ))!= (static_cast<size_t>(-1)) )
查libiconv源码：libiconv-1.16
问题原因在lib/loop_unicode.h里面

static size_t unicode_loop_convert (iconv_t icd,
                                    const char* * inbuf, size_t *inbytesleft,
                                    char* * outbuf, size_t *outbytesleft)
{
  conv_t cd = (conv_t) icd;
  size_t result = 0;
  const unsigned char* inptr = (const unsigned char*) *inbuf;
  size_t inleft = *inbytesleft;
  unsigned char* outptr = (unsigned char*) *outbuf;
  size_t outleft = *outbytesleft;
  while (inleft > 0) {
    state_t last_istate = cd->istate;
    ucs4_t wc;
    int incount;
    int outcount;
    incount = cd->ifuncs.xxx_mbtowc(cd,&wc,inptr,inleft);
    if (incount < 0) {
      if ((unsigned int)(-1-incount) % 2 == (unsigned int)(-1-RET_ILSEQ) % 2) {
        /* Case 1: invalid input, possibly after a shift sequence */
        incount = DECODE_SHIFT_ILSEQ(incount);
        if (cd->discard_ilseq) {
          switch (cd->iindex) {
            case ei_ucs4: case ei_ucs4be: case ei_ucs4le:
            case ei_utf32: case ei_utf32be: case ei_utf32le:
            case ei_ucs4internal: case ei_ucs4swapped:
              incount += 4; break;
            case ei_ucs2: case ei_ucs2be: case ei_ucs2le:
            case ei_utf16: case ei_utf16be: case ei_utf16le:
            case ei_ucs2internal: case ei_ucs2swapped:
              incount += 2; break;
            default:
              incount += 1; break;
          }
          goto outcount_zero;
        }
        #ifndef LIBICONV_PLUG
        else if (cd->fallbacks.mb_to_uc_fallback != NULL) {
          unsigned int incount2;
          struct mb_to_uc_fallback_locals locals;
          switch (cd->iindex) {
            case ei_ucs4: case ei_ucs4be: case ei_ucs4le:
            case ei_utf32: case ei_utf32be: case ei_utf32le:
            case ei_ucs4internal: case ei_ucs4swapped:
              incount2 = 4; break;
            case ei_ucs2: case ei_ucs2be: case ei_ucs2le:
            case ei_utf16: case ei_utf16be: case ei_utf16le:
            case ei_ucs2internal: case ei_ucs2swapped:
              incount2 = 2; break;
            default:
              incount2 = 1; break;
          }
          locals.l_cd = cd;
          locals.l_outbuf = outptr;
          locals.l_outbytesleft = outleft;
          locals.l_errno = 0;
          cd->fallbacks.mb_to_uc_fallback((const char*)inptr+incount, incount2,
                                          mb_to_uc_write_replacement,
                                          &locals,
                                          cd->fallbacks.data);
          if (locals.l_errno != 0) {
            inptr += incount; inleft -= incount;
            errno = locals.l_errno;
            result = -1;
            break;
          }
          incount += incount2;
          outptr = locals.l_outbuf;
          outleft = locals.l_outbytesleft;
          result += 1;
          goto outcount_zero;
        }
        #endif
        inptr += incount; inleft -= incount;
        errno = EILSEQ;
        result = -1;
        break;
      }
      if (incount == RET_TOOFEW(0)) {
        /* Case 2: not enough bytes available to detect anything */
        errno = EINVAL;
        result = -1;
        break;
      }
      /* Case 3: k bytes read, but only a shift sequence */
      incount = DECODE_TOOFEW(incount);
    } else {
      /* Case 4: k bytes read, making up a wide character */
      if (outleft == 0) {
        cd->istate = last_istate;
        errno = E2BIG;
        result = -1;
        break;
      }
      outcount = cd->ofuncs.xxx_wctomb(cd,outptr,wc,outleft);
      if (outcount != RET_ILUNI)
        goto outcount_ok;
      /* Handle Unicode tag characters (range U+E0000..U+E007F). */
      if ((wc >> 7) == (0xe0000 >> 7))
        goto outcount_zero;
      /* Try transliteration. */
      result++;
      if (cd->transliterate) {
        outcount = unicode_transliterate(cd,wc,outptr,outleft);
        if (outcount != RET_ILUNI)
          goto outcount_ok;
      }
      if (cd->discard_ilseq) {
        outcount = 0;
        goto outcount_ok;
      }
      #ifndef LIBICONV_PLUG
      else if (cd->fallbacks.uc_to_mb_fallback != NULL) {
        struct uc_to_mb_fallback_locals locals;
        locals.l_outbuf = outptr;
        locals.l_outbytesleft = outleft;
        locals.l_errno = 0;
        cd->fallbacks.uc_to_mb_fallback(wc,
                                        uc_to_mb_write_replacement,
                                        &locals,
                                        cd->fallbacks.data);
        if (locals.l_errno != 0) {
          cd->istate = last_istate;
          errno = locals.l_errno;
          return -1;
        }
        outptr = locals.l_outbuf;
        outleft = locals.l_outbytesleft;
        outcount = 0;
        goto outcount_ok;
      }
      #endif
      outcount = cd->ofuncs.xxx_wctomb(cd,outptr,0xFFFD,outleft);
      if (outcount != RET_ILUNI)
        goto outcount_ok;
      cd->istate = last_istate;
      errno = EILSEQ;
      result = -1;
      break;
    outcount_ok:
      if (outcount < 0) {
        cd->istate = last_istate;
        errno = E2BIG;
        result = -1;
        break;
      }
      #ifndef LIBICONV_PLUG
      if (cd->hooks.uc_hook)
        (*cd->hooks.uc_hook)(wc, cd->hooks.data);
      #endif
      if (!(outcount <= outleft)) abort();
      outptr += outcount; outleft -= outcount;
    }
  outcount_zero:
    if (!(incount <= inleft)) abort();
    inptr += incount; inleft -= incount;
  }
  *inbuf = (const char*) inptr;
  *inbytesleft = inleft;
  *outbuf = (char*) outptr;
  *outbytesleft = outleft;
  return result;
}

!(outcount <= outleft)和!(incount <= inleft)一直都是false，导致程序一直在里面循环一直到异常退出或者程序直接崩溃
原因是：outleft和inleft的数据类型是size_t，而outcount和incount的数据类型是int，可能是android 9的交叉编译器的size_t与android 4.4的交叉编译器的size_t不同，所以导致!(outcount <= outleft)和!(incount <= inleft)一直都是false
修改方法：将outleft和inleft定义为int