~> gdb pi
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This GDB was configured as "i386-redhat-linux-gnu"...

(gdb) list
1	#include <math.h>
2	
3	int main (){
4	
5	   int i ;
6	   double pi = 0 ;
7	
8	   for (i=0; i<10000000; i++)
9	
10	     pi += pow (-1,i) / (2*i+1) ;

(gdb) run
Starting program: /home/prof/maziero/ambiente/pi 
O valor aproximado de Pi é: 3.141593

Program exited with code 045.

(gdb) disassemble main
Dump of assembler code for function main:
0x080483ac <main+0>:	push   %ebp
0x080483ad <main+1>:	mov    %esp,%ebp
0x080483af <main+3>:	sub    $0x18,%esp
0x080483b2 <main+6>:	and    $0xfffffff0,%esp
0x080483b5 <main+9>:	mov    $0x0,%eax
0x080483ba <main+14>:	sub    %eax,%esp
0x080483bc <main+16>:	movl   $0x0,0xfffffff0(%ebp)
0x080483c3 <main+23>:	movl   $0x0,0xfffffff4(%ebp)
0x080483ca <main+30>:	movl   $0x0,0xfffffffc(%ebp)
0x080483d1 <main+37>:	cmpl   $0x98967f,0xfffffffc(%ebp)
0x080483d8 <main+44>:	jle    0x80483dc <main+48>
0x080483da <main+46>:	jmp    0x8048414 <main+104>
0x080483dc <main+48>:	fildl  0xfffffffc(%ebp)
0x080483df <main+51>:	lea    0xfffffff8(%esp,1),%esp
0x080483e3 <main+55>:	fstpl  (%esp,1)
0x080483e6 <main+58>:	push   $0xbff00000
0x080483eb <main+63>:	push   $0x0
0x080483ed <main+65>:	call   0x80482cc <pow>
0x080483f2 <main+70>:	add    $0x10,%esp
0x080483f5 <main+73>:	mov    0xfffffffc(%ebp),%eax
0x080483f8 <main+76>:	shl    %eax
0x080483fa <main+78>:	inc    %eax
0x080483fb <main+79>:	push   %eax
0x080483fc <main+80>:	fildl  (%esp,1)
0x080483ff <main+83>:	lea    0x4(%esp,1),%esp
0x08048403 <main+87>:	fdivrp %st,%st(1)
0x08048405 <main+89>:	fldl   0xfffffff0(%ebp)
0x08048408 <main+92>:	faddp  %st,%st(1)
0x0804840a <main+94>:	fstpl  0xfffffff0(%ebp)
0x0804840d <main+97>:	lea    0xfffffffc(%ebp),%eax
0x08048410 <main+100>:	incl   (%eax)
0x08048412 <main+102>:	jmp    0x80483d1 <main+37>
0x08048414 <main+104>:	fldl   0xfffffff0(%ebp)
0x08048417 <main+107>:	fldl   0x8048520
0x0804841d <main+113>:	fmulp  %st,%st(1)
0x0804841f <main+115>:	fstpl  0xfffffff0(%ebp)
0x08048422 <main+118>:	sub    $0x4,%esp
0x08048425 <main+121>:	pushl  0xfffffff4(%ebp)
0x08048428 <main+124>:	pushl  0xfffffff0(%ebp)
0x0804842b <main+127>:	push   $0x8048500
0x08048430 <main+132>:	call   0x80482ec <printf>
0x08048435 <main+137>:	add    $0x10,%esp
0x08048438 <main+140>:	leave  
0x08048439 <main+141>:	ret    
End of assembler dump.

(gdb) break main
Breakpoint 1 at 0x80483bc: file pi.c, line 6.

(gdb) run
Starting program: /home/prof/maziero/ambiente/pi 

Breakpoint 1, main () at pi.c:6
6	   double pi = 0 ;

(gdb) next
8	   for (i=0; i<10000000; i++)
(gdb) next

10	     pi += pow (-1,i) / (2*i+1) ;
(gdb) print pi

$1 = 0

(gdb) print i
$2 = 0

(gdb) next
8	   for (i=0; i<10000000; i++)

(gdb) next
10	     pi += pow (-1,i) / (2*i+1) ;

(gdb) pi rint pi
$3 = 1

(gdb) print i
$4 = 1

(gdb) cont
Continuing.
O valor aproximado de Pi é: 3.141593

Program exited with code 045.

(gdb) quit