请教一个关于 c语言 pow() 函数的问题

c语言单片机内存 math.h 我首先用如下的方式定义了几个结构体变量，并在程序中进行赋值以及使用 typedef struct { int a[6]; int b; }object; object t1,t2,t3,t4; 当我调用math.h中的pow(float x,float y)函数来进行指数计算的时候发现t3和t4中的值被改的面目全非，参数x和y只是两个常数，不和t3、t4发生关系,而pow()函数也返回了正确的结果。因为使用的单片机只有64K内存，定义的变量也很多，减少定义的变量后t3正常了，t4的值依旧会被改变。因此怀疑是在执行pow()函数的时候占用过大内存导致的。想请教一下各位大侠，C语言中是否可以指定某个变量不被更改呢，只能在代码中修改。
40分	pow Calculates x raised to the power of y. double pow( double x, double y ); Routine Required Header Compatibility pow <math.h> ANSI, Win 95, Win NT For additional compatibility information, see Compatibility in the Introduction. Libraries LIBC.LIB Single thread static library, retail version LIBCMT.LIB Multithread static library, retail version MSVCRT.LIB Import library for MSVCRT.DLL, retail version Return Value pow returns the value of xy. No error message is printed on overflow or underflow. Values of x and y Return Value of pow x < > 0 and y = 0.0 1 x = 0.0 and y = 0.0 1 x = 0.0 and y < 0 INF Parameters x Base y Exponent Remarks The pow function computes x raised to the power of y. pow does not recognize integral floating-point values greater than 264, such as 1.0E100. Example /* POW.C * */ #include <math.h> #include <stdio.h> void main( void ) { double x = 2.0, y = 3.0, z; z = pow( x, y ); printf( “%.1f to the power of %.1f is %.1f\n”, x, y, z ); } Output 2.0 to the power of 3.0 is 8.0 Floating-Point Support Routines See Also exp, log, sqrt
	To set a breakpoint when a variable changes value From the Edit menu, click Breakpoints. Click the Data tab of the Breakpoints dialog box. In the Expression text box, type the name of the variable. Click OK to set the breakpoint.

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