For how different compilers handle operator ++ and operator ++ =, the compiler operator

For how different compilers handle operator ++ and operator ++ =, the compiler operator

First, go to the Code:

#include <stdio.h>#include <iostream>using namespace std;int main(){int a = 5;printf("a++ = %d\n", a++);a = 5;printf("++a = %d\n", ++a);a = 5;printf("a += a++  =%d\n", a += a++);a = 5;printf("a += (a++)  =%d\n", a = a + (a++));a = 5;printf("a += ++a  =%d\n", a += ++a);a = 5;printf("a += (++a)  =%d\n", a += (++a));a = 5;printf("++a += a++ =%d\n", ++a += a++);a = 5;printf("(++a) += (a++) =%d\n", (++a) += (a++));return 1;}

I don't know what the readers think. What do you think is their output value?

The running result of VS2013 and the running result compiled by g ++ 4.8.2 are directly provided:

For different results, let's take a look at the assembly code (only the [printf ("a + = a ++ = % d \ n ", a + = a ++);] Partial Assembly is used as an example. You can take a look at it by yourself ):

/* vs2013 */    13: printf("a += a++  =%d\n", a += a++);011ECAC7  mov         eax,dword ptr [a]  011ECACA  add         eax,dword ptr [a]  011ECACD  mov         dword ptr [a],eax  011ECAD0  mov         ecx,dword ptr [a]  011ECAD3  mov         dword ptr [ebp-0D0h],ecx  011ECAD9  mov         edx,dword ptr [a]  011ECADC  add         edx,1  011ECADF  mov         dword ptr [a],edx  011ECAE2  mov         esi,esp  011ECAE4  mov         eax,dword ptr [ebp-0D0h]  011ECAEA  push        eax  011ECAEB  push        11F832Ch  011ECAF0  call        dword ptr ds:[11FC1E4h]  011ECAF6  add         esp,8  011ECAF9  cmp         esi,esp  011ECAFB  call        __RTC_CheckEsp (011E1631h)  

/* g++ 4.8.2 */13printf("a += a++  =%d\n", a += a++);   0x08048602 <+85>:mov    0x1c(%esp),%eax   0x08048606 <+89>:lea    0x1(%eax),%edx   0x08048609 <+92>:mov    %edx,0x1c(%esp)   0x0804860d <+96>:add    %eax,0x1c(%esp)   0x08048611 <+100>:mov    0x1c(%esp),%eax   0x08048615 <+104>:mov    %eax,0x4(%esp)   0x08048619 <+108>:movl   $0x8048814,(%esp)   0x08048620 <+115>:call   0x80484a0 <printf@plt>

I have read a few books, but the compilation is more self-developed. I hope you can help me explain the situation ~~~, Thank you!

[Note] the above Code running platform is a 32-bit operating system. vs2013 runs on Windows 8.1 Enterprise Edition, and g ++ runs on ubuntu14.04 (3.20.- 41-generic)