One guidelines for C/C++ programmer
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Johann Gerell wrote:
Guideline 1: Always compile cleanly on warning level 4.
Gudeline 2: Turn on the option: "Treat warnings as errors".
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Guideline 1: Always compile cleanly on warning level 4.
-- Time you enjoy wasting is not wasted time - Bertrand Russel
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Actually, writing if (x = 0) ... does not generate any warning at all (at least in VS 2005). Looks like this is a flaw in the compilor.
ed welch wrote:
Actually, writing if (x = 0) ... does not generate any warning at all (at least in VS 2005).
Of course it does. But you have to enable warning level 4 (as I pointed out in the "guideline") in the project property pages under C/C++ > General. Then you get this:
warning C4706: assignment within conditional expression
If you also set that warnings should be treated as errors, you get this:
error C2220: warning treated as error - no 'object' file generated
warning C4706: assignment within conditional expressionand that way you just cannot miss the assignment.
-- Time you enjoy wasting is not wasted time - Bertrand Russel
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Actually, writing if (x = 0) ... does not generate any warning at all (at least in VS 2005). Looks like this is a flaw in the compilor.
Depends on the compiler: Borland C++ 5.5 for Win32 reports: Warning W8060 xtc.c 14: Possibly incorrect assignment in function main As usual, HP C V7.3-009 on OpenVMS Alpha V8.3 takes it to a whole other level: CHECK Messages reporting code or practices that, although correct and perhaps portable, are sometimes considered ill-advised because they can be confusing or fragile to maintain. For example, assignment as the test expression in an "if" statement. NOTE: The check group gets defined by enabling LEVEL5 messages. LEVEL4 Useful check/portable messages. LEVEL5 Not so useful check/portable messages. CC/WARNING=(ENABLE=LEVEL5,VERBOSE) TEST.C if ( argc = 1 ) ....^ %CC-I-CONTROLASSIGN, In this statement, the assignment expression "argc=1" is used as the controlling expression of an if, while or for statement. at line number 14 in file MY$ROOT:[000000]TEST.C;2 Description: A common user mistake is to accidentally use assignment operator "=" instead of the equality operator "==" in an expression that controls a transfer. For example sayin g if (a = b) instead of if (a == b). While using the assignment operator is valid, it is often not what was intended. When this message is enabled, the compiler will detect these cases at compile-time. This can often avoid long debugging sessions needed to find the bug in the user's program. User Action: Make sure that the assignment operator is what is expected. printf ( "Hello, %s!" , argv [ 1 ] ) ; ........^ %CC-I-IGNORECALLVAL, In this statement, the value returned from the function "printf(...)" is not used - if this is intended, it should be cast to "void". at line number 16 in file MY$ROOT:[000000]TEST.C;2 Description: A function that returns a value has been invoked, yet the value was not used. This might not have been what you intended. User Action: Cast the function to void to suppress the message. CC/WARNING=(ENABLE=CONTROLASSIGN) TEST.C if ( argc = 1 ) ....^ %CC-I-CONTROLASSIGN, In this statement, the assignment expression "argc=1" is used as the controlling expression of an if, while or for statement. at line number 14 in file MY$ROOT:[000000]TEST.C;2
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Depends on the compiler: Borland C++ 5.5 for Win32 reports: Warning W8060 xtc.c 14: Possibly incorrect assignment in function main As usual, HP C V7.3-009 on OpenVMS Alpha V8.3 takes it to a whole other level: CHECK Messages reporting code or practices that, although correct and perhaps portable, are sometimes considered ill-advised because they can be confusing or fragile to maintain. For example, assignment as the test expression in an "if" statement. NOTE: The check group gets defined by enabling LEVEL5 messages. LEVEL4 Useful check/portable messages. LEVEL5 Not so useful check/portable messages. CC/WARNING=(ENABLE=LEVEL5,VERBOSE) TEST.C if ( argc = 1 ) ....^ %CC-I-CONTROLASSIGN, In this statement, the assignment expression "argc=1" is used as the controlling expression of an if, while or for statement. at line number 14 in file MY$ROOT:[000000]TEST.C;2 Description: A common user mistake is to accidentally use assignment operator "=" instead of the equality operator "==" in an expression that controls a transfer. For example sayin g if (a = b) instead of if (a == b). While using the assignment operator is valid, it is often not what was intended. When this message is enabled, the compiler will detect these cases at compile-time. This can often avoid long debugging sessions needed to find the bug in the user's program. User Action: Make sure that the assignment operator is what is expected. printf ( "Hello, %s!" , argv [ 1 ] ) ; ........^ %CC-I-IGNORECALLVAL, In this statement, the value returned from the function "printf(...)" is not used - if this is intended, it should be cast to "void". at line number 16 in file MY$ROOT:[000000]TEST.C;2 Description: A function that returns a value has been invoked, yet the value was not used. This might not have been what you intended. User Action: Cast the function to void to suppress the message. CC/WARNING=(ENABLE=CONTROLASSIGN) TEST.C if ( argc = 1 ) ....^ %CC-I-CONTROLASSIGN, In this statement, the assignment expression "argc=1" is used as the controlling expression of an if, while or for statement. at line number 14 in file MY$ROOT:[000000]TEST.C;2
PIEBALDconsult wrote:
As usual, HP C V7.3-009 on OpenVMS Alpha V8.3 takes it to a whole other level:
Wow! I wonder how much money HP could get by porting their warning reporter into a visual studio plugin?
Today's lesson is brought to you by the word "niggardly". Remember kids, don't attribute to racism what can be explained by Scandinavian language roots. -- Robert Royall
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Johann Gerell wrote:
Guideline 1: Always compile cleanly on warning level 4.
Gudeline 2: Turn on the option: "Treat warnings as errors".
Nemanja Trifunovic wrote:
Gudeline 2: Turn on the option: "Treat warnings as errors".
I do that for release builds, but not debug.
Anyone who thinks he has a better idea of what's good for people than people do is a swine. - P.J. O'Rourke
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asadullah ansari wrote:
minimize manpower
Hence not a real-men company! BTW What is the point on minimizing manpower in software industry? Our work is creative after all, don't you agree? The Software Laborer :-D
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
[My articles]We should create the union of real men, excuse me, C programmers. We'd fight to protect our jobs, our interests and our bugs!
To those who understand, I extend my hand. To the doubtful I demand: Take me as I am. Not under your command, I know where I stand. I won't change to fit yout plan. Take me as I am.
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LOL. I remember someone suggesting defines like this:
#define please
#define thanksAnd the code would be much more pleasant to read:
please do {
...
} while (i < imax);
thanks -
We should create the union of real men, excuse me, C programmers. We'd fight to protect our jobs, our interests and our bugs!
To those who understand, I extend my hand. To the doubtful I demand: Take me as I am. Not under your command, I know where I stand. I won't change to fit yout plan. Take me as I am.
leonej_dt wrote:
We should create the union of real men, excuse me, C programmers.
Definitely. :-D
leonej_dt wrote:
We'd fight to protect our jobs,
That's not needed. Other 'programmers' with their 'masterpieces' ;P keep our jobs safe. :laugh:
leonej_dt wrote:
We'd fight to protect our our interests and our bugs!
Definitely again. :-D
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
[My articles] -
In your project, If you are using if condition like
enum
{
Blue_c,
Yellow_c,
Red_c
};
int color;if( color == yellow_c)
{
.....
......
}
or
if(color != Red_c)
{
....
.....
}Now you know by mistake if you forget one = or ! means if(color = yellow_c) or if(color = Red_c) then no error will come and bug fixing cost for your projects So To avoid this cost you should use
if(yellow_c == color)
{
.....
......
}
or
if(Red_c != color)
{
....
.....
}Now if you forgot to put one = ot ! then compilation error will come.. So this should be in coding standard to use like this...
Truth Can'nt be changed
Yes, this is a decent standard, and has been recommended by some very prestigious programmers (Allen Holub comes to mind).
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That's correct, in fact here we encourage people to use the most ugly, unwell formed and disaster bringing code that they may come up to. ;P
Learn from the mistakes of others, you may not live long enough to make them all yourself.
BadKarma wrote:
That's correct, in fact here we encourage people to use the most ugly, unwell formed and disaster bringing code that they may come up to.
I think you should have had some coffee before making this statement, as he is exactly right. Placing the constant first will catch this error, which is one of the common typographic errors in C-style languages.
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asadullah ansari wrote:
minimize manpower
Hence not a real-men company! BTW What is the point on minimizing manpower in software industry? Our work is creative after all, don't you agree? The Software Laborer :-D
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
[My articles]CPallini wrote:
BTW What is the point on minimizing manpower in software industry? Our work is creative after all, don't you agree? The Software Laborer
*SEXIST STATEMENT WARNING* I like to maximize the girl power in my environment...as long as I get to stick around as the token alpha male :laugh: *END SEXIST STATEMENT*
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Oh, a coding standards horror. That only works when comparing an Lvalue and an Rvalue, and if a programmer can remember to do that, then he can remember to use the correct operator in the first place. Newbies will continue to screw it up, and experienced programmers will continue to get it right the first time. One company I worked for did have that in the coding standard, but even the guy who defined the standards admitted that it was pretty useless. If it causes you trouble you could switch to D, which will throw an error if it's not done right (if I recall correctly).
PIEBALDconsult wrote:
That only works when comparing an Lvalue and an Rvalue, and if a programmer can remember to do that, then he can remember to use the correct operator in the first place. Newbies will continue to screw it up, and experienced programmers will continue to get it right the first time.
You've obviously never worked a 48-hour day.
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Yes, because actually looking at your warnings is apparently too difficult.
Anyone who thinks he has a better idea of what's good for people than people do is a swine. - P.J. O'Rourke
Joe Woodbury wrote:
Yes, because actually looking at your warnings is apparently too difficult.
I had a manager once, who was quite skilled in C programming, but who would often leave warnings in his code if he thought they were trivial...which left him open to missing new warnings that weren't. He's a lawyer now.
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PIEBALDconsult wrote:
That only works when comparing an Lvalue and an Rvalue, and if a programmer can remember to do that, then he can remember to use the correct operator in the first place. Newbies will continue to screw it up, and experienced programmers will continue to get it right the first time.
You've obviously never worked a 48-hour day.
No, uh uh. The longest day I ever worked was 28 hours... and I fell asleep.
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Real
Cprogrammers (i.e. real men) don't use such girly tricks. They bravely make mistakes whenever is needed. ;PIf the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
[My articles] -
In your project, If you are using if condition like
enum
{
Blue_c,
Yellow_c,
Red_c
};
int color;if( color == yellow_c)
{
.....
......
}
or
if(color != Red_c)
{
....
.....
}Now you know by mistake if you forget one = or ! means if(color = yellow_c) or if(color = Red_c) then no error will come and bug fixing cost for your projects So To avoid this cost you should use
if(yellow_c == color)
{
.....
......
}
or
if(Red_c != color)
{
....
.....
}Now if you forgot to put one = ot ! then compilation error will come.. So this should be in coding standard to use like this...
Truth Can'nt be changed
No, I will never do this. I would leave the job interview if I was 'corrected' on this when I wrote code.
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ed welch wrote:
Actually, writing if (x = 0) ... does not generate any warning at all (at least in VS 2005).
Of course it does. But you have to enable warning level 4 (as I pointed out in the "guideline") in the project property pages under C/C++ > General. Then you get this:
warning C4706: assignment within conditional expression
If you also set that warnings should be treated as errors, you get this:
error C2220: warning treated as error - no 'object' file generated
warning C4706: assignment within conditional expressionand that way you just cannot miss the assignment.
-- Time you enjoy wasting is not wasted time - Bertrand Russel
first thing if programmer is dump then he can make any mistake... No one gud programmer will do this sort of mistake... So Guidelines for stupid programmer only... As u know why this guidlines.. if(0 == x) : should use as guidelines if(x == 0) : should not use why first one is appreciated for stupid programmer coz he may write as if(0 = x) then error will come in this case in all compiler and second one will not give any error in max compiler...What hell this goin on...How any programmer do this mistake??? I cannt believe...
Truth Can'nt be changed
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first thing if programmer is dump then he can make any mistake... No one gud programmer will do this sort of mistake... So Guidelines for stupid programmer only... As u know why this guidlines.. if(0 == x) : should use as guidelines if(x == 0) : should not use why first one is appreciated for stupid programmer coz he may write as if(0 = x) then error will come in this case in all compiler and second one will not give any error in max compiler...What hell this goin on...How any programmer do this mistake??? I cannt believe...
Truth Can'nt be changed
The problem with
if(0 == x)is that we don't naturally read or write that way. It's Yoda-speak[^]:if x is 0will becomeif 0, x is. ;P Unnatural actions have a tendency to not stick naturally.Time you enjoy wasting is not wasted time - Bertrand Russel