功能参数最大数 [英] Function parameters max number

问题描述

我没有找到在C99标准计数功能参数的任何限制，我想这只能通过堆栈大小的限制。

不过，我已经写了一个简单的测试程序来演示用的参数大计数功能的行为。当其10K左右，我得到（在Cygwin的gcc版本4.5.3）上GCC以下错误：

  /usr/lib/gcc/i686-pc-cygwin/4.5.3 /../../../ libcygwin.a（libcmain.o）:(。文本+ 0xa9）：未定义的引用`_WinMain @ 16
 

我认识到的参数，大计数是不可能的，但我不知道什么参数的编译器来确定这个限制？

修改

脚本生成C代码

 ＃！/ bin / sh的NUM = $ 1回声＆GT; out.c
回声的#include＆LT;＆stdio.h中GT; ＆GT;＆GT; out.c回声INT getsum（＆GT;＆GT; out.cI = 0
而[$ I $ -lt NUM]
做
    （（我+ +））
    如果[$ I $ -eq NUM]
    然后
        回声INT p $ I）＆GT;＆GT; out.c
    其他
        回声-neINT p $ I，＆GT;＆GT; out.c
    科幻
DONE回声{＆GT;＆GT; out.c回声-ne回归＆GT;＆GT; out.cI = 0
而[$ I $ -lt NUM]
做
    （（我+ +））
        如果[$ I $ -eq NUM]
        然后
                回声P $ I; ＆GT;＆GT; out.c
        其他
                回声-neP $ I +＆GT;＆GT; out.c
        科幻
DONE回声}＆GT;＆GT; out.c回声INT的main（）{＆GT;＆GT; out.c
回声％d个元素的printf（\\总和为％d \\，$ num个，getsum（＆GT;＆GT; out.cI = 0
而[$ I $ -lt NUM]
做
        （（我+ +））
        如果[$ I $ -eq NUM]
        然后
                回声$ I＆GT;＆GT; out.c
        其他
                回声-ne$ I＆GT;＆GT; out.c
        科幻
DONE回声））; ＆GT;＆GT; out.c回声返回0;}＆GT;＆GT; out.c
GCC out.c
./a.exe
 

解决方案

本标准规定一定的最低数量每它实现必须支持，

5.2.4.1翻译限制

  

- 127参数函数定义结果
   - 127论点一个函数调用

I did not find any limitation of count function parameters in the C99 standard and I guess it is only limited by stack size.

However I've written a simple test program to demonstrate the behavior of a function with a large count of parameters. When its about 10k, I get the following error on gcc (gcc version 4.5.3 on Cygwin):

/usr/lib/gcc/i686-pc-cygwin/4.5.3/../../../libcygwin.a(libcmain.o):(.text+0xa9): undefined reference to `_WinMain@16'

I realize that such large count of parameters is unlikely but I wonder what parameter of the compiler determines this limit?

EDIT

script to generate C-source

#!/bin/sh

num=$1

echo "" > out.c
echo "#include <stdio.h>" >> out.c

echo "int getsum( " >> out.c

i=0
while [ $i -lt $num ]
do
    ((i++))
    if [ $i -eq $num ] 
    then
        echo "int p$i )" >> out.c
    else 
        echo -ne "int p$i," >> out.c
    fi
done

echo "{" >> out.c

echo -ne "  return " >> out.c

i=0
while [ $i -lt $num ]
do
    ((i++))
        if [ $i -eq $num ]
        then
                echo "p$i;" >> out.c
        else
                echo -ne "p$i + " >> out.c
        fi
done

echo "}" >> out.c

echo "int main(){"  >> out.c
echo "printf(\"Sum of %d elements is %d\", $num, getsum(" >> out.c 

i=0
while [ $i -lt $num ]
do
        ((i++))
        if [ $i -eq $num ]
        then
                echo "$i" >> out.c
        else
                echo -ne "$i," >> out.c
        fi
done

echo "));" >> out.c

echo "return 0;}" >> out.c
gcc out.c
./a.exe

解决方案

The Standard specifies a certain minimum number which every implementation must support,

5.2.4.1 Translation Limits

— 127 parameters in one function definition
— 127 arguments in one function call

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