Lundin‭

The C standard does not speak of "errors" and "warnings", those are not formal terms. The compiler is only required to produce a diagnostic message, as specified in C11 5.1.1.3: Diagnostics A c...

posted 2y ago by Lundin‭  ·  edited 1y ago by hkotsubo‭

So it appears that we've gotten our first "company tag", Apple. We know from SO that company name tags were always problematic since: Questions are about products, not companies. Given that the pr...

1 answer  ·  posted 2y ago by Lundin‭  ·  last activity 2y ago by Alexei‭

What exactly must a C compiler do when it finds a compile-time error? The most obvious kind of errors are language syntax errors, but the C standard also speaks of constraints, which are rules tha...

1 answer  ·  posted 2y ago by Lundin‭  ·  edited 1y ago by ghost-in-the-zsh‭

"Stack vs heap" is a common over-simplification and not really a meaningful one, since those two areas have quite different, specialized uses. And no, those are not the only memory regions used by ...

posted 2y ago by Lundin‭  ·  edited 2y ago by sth‭

The concept you are looking for is referred to as opaque type or opaque pointers. This is the proper method to achieve private encapsulation in C and can also be used for inheritance/polymorphism (...

posted 1y ago by Lundin‭  ·  edited 4mo ago by Lundin‭

Undefined behavior (informally "UB") is a formal term in the C language, defined in C17 3.4.3 undefined behavior behavior, upon use of a nonportable or erroneous program construct or of erroneous ...

posted 2y ago by Lundin‭  ·  edited 2y ago by Lundin‭

We can't go and shamelessly promote Codidact in SO comments etc just for the sake of it - that's regarded as spamming and might get you banned, plus it will give Codidact a nasty rep. Similarly, SE...

posted 2y ago by Lundin‭  ·  edited 2y ago by Lundin‭

My recommended beginner setup for gcc-like compilers is: -std=c11 -pedantic-errors -Wall -Wextra -Werror Here is an explanation of what these options do: -std=c11. gcc & friends are by d...

posted 1y ago by Lundin‭

I heard rumours that the strcpy function is dangerous and shouldn't be used. Supposedly it can be exploited to create buffer overflows somehow. And indeed when I compile my C code in the admittedl...

1 answer  ·  posted 1y ago by Lundin‭  ·  last activity 1y ago by J-hen‭

When reading questions about C programming from beginners, I very often see them describing peculiar run-time errors and crashes, segmentation faults and similar. They have spent a lot of time chas...

1 answer  ·  posted 1y ago by Lundin‭  ·  edited 1y ago by Lundin‭

I have created this sensational program: #include <stdio.h> int* func (void) { int local=5; return &local; } int main (void) { printf("%d\n", *func()); } This prints 5 even thoug...

1 answer  ·  posted 2y ago by Lundin‭  ·  last activity 2y ago by Lundin‭

Not using braces is considered bad practice by widely recognized industry coding standards (MISRA-C:2012 rule, 15.6, CERT C EXP19-C and others). Once upon a time I liked to skip out braces too, bu...

posted 2y ago by Lundin‭  ·  edited 1y ago by Lundin‭

This goes back to the various CPU architecture "wars" in the 1970s-1980s between the competitors Intel and Motorola (for example Intel 8086 vs Motorola 68000). For various reasons, CPUs from these ...

posted 2y ago by Lundin‭  ·  edited 2y ago by Lundin‭

Generally speaking, pointer arithmetic is undefined behavior unless carried out on arrays. This is how the additive operators behave, C17 6.5.6: For the purposes of these operators, a pointer to...

posted 12mo ago by Lundin‭  ·  edited 12mo ago by Lundin‭

When writing any form of custom function such as this: void func (int* a, int* b) Should I add code to check if a and b are null pointers or not? if(a == NULL) /* error handling */ When po...

4 answers  ·  posted 8mo ago by Lundin‭  ·  last activity 8mo ago by Dirk Herrmann‭