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Empirical Study On How C Devs Use Goto In Practice Says "Not Harmful"
Edsger Dijkstra famously opined in 1968 on the danger of Goto statements. New submitter Mei Nagappan writes with a mellower view, nearly 50 years later: By qualitatively and quantitatively analyzing a statistically valid random sample from almost 2 million C files and 11K+ projects, we find that developers limit themselves to using goto appropriately in most cases, and not in an unrestricted manner like Dijkstra feared, thus suggesting that goto does not appear to be harmful in practice.
(Here's the preprint linked from above abstract.)
Is that because they were warned by Djikstra that it would be harmful to use it haphazardly?
Programmers are more used to structuring their code (using functions, modules, etc.) and using best practices (minimizing globals, separation of concerns, etc.). This was not so much the case in the late 60's. That, combined with the "goto stigma", means that average developers avoid goto usage and good developers know when it's worth it.
We saw a similar backlash with the concept of operator overloading. People abused it in C++, the Java designers overreacted and prohibited it, but most languages since then recognize that "yeah, operator overloading's really nice when you're building an API for mathematical constructs" (like complex numbers, quaternions, and matrices). So it's there in C#, Python, D, Rust, Scala, but (from the little I've seen) people seldom abuse it these days.
-1, Too Many Layers Of Abstraction
As someone who saw the programming practices of the 1960s and early 1970s, I can assure you that Dijkstra's warning was needed.
It caused a massive change in practices among software professionals, within a few years GOTO had almost disappeared from most new code.
I remember seeing code from a "sales engineer" in 1975 that was so full of buggy gotos that we refused to even attempt to debug it.
He learned.
Really? You loose point for what is really the most sane way to handle cleanup in C? Have the instructors in those courses actually done any real work outside of academia? This is a very common pattern that I've seen in almost every large C code base that I've worked on.
static int
do_some_work (context_t context,
int x,
error_t **error)
{
int rv = 0;
database_t *db;
data_t v;
db = get_db (context, error);
do some work ...
v = compute_v (context, db, error);
if (!v)
goto out;
more work ...
out:
return rv;
}
It makes it so much cleaner and easier to read.