Question

http://www.ohchr.org。

The following code work as expected in g++ 4.4.0 under mingw32:

#include <cstdio>
int main()
  {
  long long x = 0xdeadbeefc0defaceLL ;
  printf ("%llx
", x) ;
  }

但是,如果我能够用<代码>-Wall发出所有警告,那么它就说:

f.cpp: In function  int main() :
f.cpp:5: warning: unknown conversion type character  l  in format
f.cpp:5: warning: too many arguments for format

该编码与<代码>%lld相同。这是否在新版本中确定?

Edited again to add:
The warning doesn t go away if I specify -std=c++0x, even though (i) long long is a standard type, and (ii) %lld and %llx seem to be officially supported. For instance, from 21.5 Numeric conversions para 7:

Each function returns a string object holding the character representation of the value of its argument that would be generated by calling sprintf(buf, fmt, val) with a format specifier of "%d", "%u", "%ld", "%lu", "%lld", "%llu", "%f", "%f", or "%Lf", respectively, where buf designates an internal character buffer of sufficient size.

因此,这确实是一个 b?

Answer 1

long long x = 0xdeadbeefc0defaceLL; // note LL in the end

没有<代码>ll 长度查询仪。最好的是:

printf ("%lx
", x); // l is for long int

I ve tested your sample on my g++, it compiles without errors even without -std=c++0x flag:

~$ g++ -Wall test.cpp
~$ g++ --version
g++ (Ubuntu 4.4.3-4ubuntu5) 4.4.3

So, yes, this fixed in newer versions.

Answer 2

For first warning I can say that you must use 0xdeadbeefc0defaceLL instead of 0xdeadbeefc0deface. After that other warnings may pass also.

Answer 3

I get the same warning compiling C using windows/mingw32.

warning: unknown conversion type character  l  in format

So yes, probably a compiler/platform specific bug.

Answer 4

It s a Mingw-specific issue, because it calls the native Windows runtime for certain things, including this. See this answer.

%I64d works for me. In the answer linked above there is a more portable albeit less readable solution as well.

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