Memory leak proof every C program
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Memory leak proof every C program
1–10 of 175 posts
Re: Memory leak proof every C program
#2This solution doesn't do anything to prevent leaking memory in anything but the most pedantic sense, and actually creates leaks and dangling pointers.
The function just indirects malloc with a wrapper so that all of the memory is traversable by the "bigbucket" structure. Memory is still leaked in the sense that any unfreed data will continue to consume heap memory and will still be inaccessible to the code unless the application does something with the "bigbucket" structure--which it can't safely do (see below).
There is no corresponding free() call, so data put into the "bigbucket" structure is never removed, even when the memory allocation is freed by the application. This, by definition, is a leak, which is ironic.
In an application that does a lot of allocations, the "bigbucket" structure could exhaust the heap even though there are zero memory leaks in the code. Consider the program:
int main(int argc, char** argv) {
for (long i = 0; i There are already tools to identify memory leaks, such as LeakSanitiser https://clang.llvm.org/docs/LeakSanitizer.html. Use those instead.
Re: Memory leak proof every C program
#3This is the core idea:
> It is [...] entirely optional to call free. If you don’t call free, memory usage will increase over time, but technically, it’s not a leak. As an optimization, you may choose to call free to reduce memory, but again, strictly optional.
This is beautiful! Unless your program is long-running, there's no point of ever calling free in your C programs. The system will free the memory for you when the program ends. Free-less C programming is an exhilarating experience that I recommend to anybody.
In the rare cases where your program needs to be long-running, leaks may become a real problem. In that case, it's better to write a long-running shell script that calls a pipeline of elegant free-less C programs.
Re: Memory leak proof every C program
#4[flagged]
Re: Memory leak proof every C program
#5This is not thread safe.
Re: Memory leak proof every C program
#6[flagged]
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Re: Memory leak proof every C program
#7This is the core idea: > It is [...] entirely optional to call free. If you don’t call free, memory usage will increase over time, but technically, it’s not a leak. As an optimization, you may choose to call free to reduce memory, but again, strictly optional. This is beautiful! Unless your program is long-running, there's no point of ever calling free in your C programs. The system will free the memory for you when…
In the not-rare case where you're writing a library, or wrapping a utility, the last programmer's exhilaration is your pain.
Re: Memory leak proof every C program
#8This is the core idea: > It is [...] entirely optional to call free. If you don’t call free, memory usage will increase over time, but technically, it’s not a leak. As an optimization, you may choose to call free to reduce memory, but again, strictly optional. This is beautiful! Unless your program is long-running, there's no point of ever calling free in your C programs. The system will free the memory for you when…
Next thing they do is to optimize the hell out of kernel process management things until it catches up with the overhead of calling a function in a GC language.
Re: Memory leak proof every C program
#9All arena-apologists hate this little trick
Re: Memory leak proof every C program
#10I bet this is what some people on my team would come up with if the ticket acceptance criteria said "program must not leak memory when checked with valgrind"