Hi,

The -fwrapv documentation states: 
This option instructs the compiler to assume that signed arithmetic ov
+erflow of addition, subtraction and multiplication wraps around using
+ twos-complement representation.

[download]
I thought that this was the usual (default) behaviour, anyway. And some quick experimentation I've done supports that notion.
So, why is the flag specified on so many gcc bulds of perl (eg Windows and Ubuntu) ?

Is it just a case of deciding that the perl flags might as well be open and specific about this ?
Perhaps -fwrapv is present simply to alert us to the fact that another option (-ftrapv) is available ? (Not that I think you'd want to build perl with -ftrapv)
Or are there actually cases where -fwrapv is not the gcc default ?

Cheers,
Rob

PS: For those curious, the -ftrapv documentation states: 
This option generates traps for signed overflow on addition, subtracti
+on, multiplication operations.

[download]
The documentation also points out that -ftrapv and -fwrapv override each other - ie, you can have one or the other, but not both.

In reply to Why does $Config{ccflags} include "-fwrapv" on many gcc builds of perl ? by syphilis

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