Questions tagged [observable-behavior]
3 questions
11
votes
5 answers
Is printing an empty string observable behavior in C++?
In C++03 Standard observable behavior (1.9/6) includes calls to library I/O functions. Now I have this code:
printf( "" );
which is formally a call to a library I/O function but has no effect.
Is it observable behavior? Is the compiler allowed to…
sharptooth
- 167,383
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7
votes
1 answer
Does any change in program state constitute observable behavior?
Consider the two following programs:
program one
int main()
{
printf( "hello\n" );
}
program two
int main()
{
srand( 0 );
if( rand() ) {
printf( "hello\n" );
} else {
printf( "hello\n" );
}
}
Do they have the same…
sharptooth
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- 100
- 513
- 979
-1
votes
2 answers
Is this compiler optimization inconsistency entirely explained by undefined behaviour?
During a discussion I had with a couple of colleagues the other day I threw together a piece of code in C++ to illustrate a memory access violation.
I am currently in the process of slowly returning to C++ after a long spell of almost exclusively…
TerraPass
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