看一下下面的代码（当然包括错误，以检验splint的功能）：
#include
int main(int argc,char* argv[]){
int a=100; /*没有使用的变量*/
int b[8];
printf("Hello c\n");
b[9]=100; /*明显数组越界 */
/* 用到了两个为声明的变量c和d/
c=100;
d=10;
return 0;
}
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现在可以用splint来检查一下，为了检验是否可以检测到数组越界，使用+bounds选项。
splint hi.c +bounds
输出结果：
hi.c: (in function main)
hi.c:9:2: Unrecognized identifier: c
Identifier used in code has not been declared. (Use -unrecog to inhibit
warning)
hi.c:10:2: Unrecognized identifier: d
hi.c:4:6: Variable a declared but not used
A variable is declared but never used. Use /*@unused@*/ in front of
declaration to suppress message. (Use -varuse to inhibit warning)
hi.c:7:2: Likely out-of-bounds store:
b[9]
Unable to resolve constraint:
requires 7 >= 9
needed to satisfy precondition:
requires maxSet(b @ hi.c:7:2) >= 9
A memory write may write to an address beyond the allocated buffer. (Use
-likely-boundswrite to inhibit warning)
hi.c:3:14: Parameter argc not used
A function parameter is not used in the body of the function. If the argument
is needed for type compatibility or future plans, use /*@unused@*/ in the
argument declaration. (Use -paramuse to inhibit warning)
hi.c:3:25: Parameter argv not used
Finished checking --- 6 code warnings
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现在详细看一下结果：
检查结果1：
hi.c:9:2: Unrecognized identifier: c
Identifier used in code has not been declared. (Use -unrecog to inhibit
warning)
hi.c:10:2: Unrecognized identifier: d
hi.c:4:6: Variable a declared but not used
A variable is declared but never used. Use /*@unused@*/ in front of
declaration to suppress message. (Use -varuse to inhibit warning)
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这些应该是splint检测到变量c和d没有声明。
检查结果2：
hi.c:7:2: Likely out-of-bounds store:
b[9]
Unable to resolve constraint:
requires 7 >= 9
needed to satisfy precondition:
requires maxSet(b @ hi.c:7:2) >= 9
A memory write may write to an address beyond the allocated buffer. (Use
-likely-boundswrite to inhibit warning)
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这些是检查存在数组越界，因为吧b[8]的最大数组序号应该是7，而不是9，所以出现requires 7 >= 9；
检查结果3：
hi.c:3:14: Parameter argc not used
A function parameter is not used in the body of the function. If the argument
is needed for type compatibility or future plans, use /*@unused@*/ in the
argument declaration. (Use -paramuse to inhibit warning)
hi.c:3:25: Parameter argv not used
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这些表明argc和argv变量声明了，但是没有使用。这个不是什么问题。
如果小心使用splint，应该对于c语言的程序编写有非常大的辅助作用！
（责任编辑：云子）
