azonenberg, 4 days ago (edited 4 days ago)

class FaultDisabler
{
public:
FaultDisabler() { sr = SCB_DisableDataFaults(); }
~FaultDisabler() { SCB_EnableDataFaults(sr);}
protected:
uint32_t sr;
};

#define unsafe FaultDisabler fd;

nolanl, 4 days ago

@azonenberg Is that #define correct?

It looks like:
unsafe {
code();
}
expands to:
FaultDisabler fd; {
code();
}

and so the RAII object is outside the {} scope, and thus lives past the } and until the enclosing scope is exited...

JeremiahFieldhaven, 9 days ago

@psychicparrot42 #define CreateDefaultSubObject CreateDefaultSubobject

There you go!

(Please don't do this)

rep_of_a, 14 days ago

@raodaozao @vfig I'm quite agressive in my my math code with epsilon, and unfortunatly the 10 years that past since I wrote all that I can't remember why, but almost certain its todo with comparisons.

#define ROA_EPSILON (0.0000001f)

if(vec3_equals_vec3(a,b)) {

}

Doomed_Daniel, 16 days ago

Huh, just realized that all X macro examples I could find use exactly one name for the entries (often "X") - I found using several for different purposes, like different member types to (de)serialize, very useful - is this really unusual or did I just not look hard enough?

Example:

#define D3_IMSTYLE_ATTRS \
D3_IMATTR_FLOAT ( Alpha ) \
D3_IMATTR_FLOAT( DisabledAlpha ) \
D3_IMATTR_VEC2( WindowPadding ) \
D3_IMATTR_INT( ColorButtonPosition )

etc

Doomed_Daniel, 16 days ago

(and then I #define D3_IMATTR_FLOAT(NAME), D3_IMATTR_VEC2(NAME) and D3_IMATTR_INT(NAME) however I need it to print/write or parse or whatever, before just putting "D3_IMSTYLE_ATTRS" in a line that then expands all that)

The X Macro examples/articles I found would instead probably use X(NAME, TYPE, SCANFSTR, PRINTFSTR) or sth like that instead of D3_IMATTR_FLOAT(NAME), D3_IMATTR_VEC2(NAME) etc, which would've been more painful overall, IMO

Doomed_Daniel, 16 days ago

Apart from this, I must admit I'm a bit proud of my hack to check if my table that mirrors a (thankfully continuous) enum is complete:

#define D3_IMSTYLE_COLOR(C) + 1

static_assert( ImGuiCol_COUNT == 0 D3_IMSTYLE_COLORS, "something was added or removed in enum ImGuiCol_ => adjust D3_IMSTYLE_COLORS table above" );

"0 D3_IMSTYLE_COLORS" is expanded to 0 + 1 + 1 + ... for each D3_IMSTYLE_COLOR entry

rygorous, 27 days ago

@pervognsen @danluu It doesn't really work well to define it that way on two's complement targets though.

E.g. the canonical way to #define INT_MIN on 32-bit C targets is (-0x7fffffff - 1) or similar. You can't write (-0x80000000) since the 0x80000000 is too large for int32 so it forces the constant to be unsigned, and then you end up with the wrong type.

lanodan, 1 month ago

Heck of a stub mount:

#define _GNU_SOURCE
<a class="hashtag" data-tag="include" href="https://queer.hacktivis.me/tag/include">#include</a> <sys/mount.h>
int
main() {
        return mount("/dev/sda", "/oasis", "ext4", 0, 0);
}

(Wrote it with ed(1), even if I likely could get vis at this point)

stungeye, 1 month ago

@raptor85 Oh, thanks! This is great info. I used WinMain as a way of getting rid of the extra console terminal that was opening up along with the SDL window.

Also, when I had my own main() I got a compiler error that I could only get rid of by adding a #define SDL_MAIN_HANDLED before the SDL.h include. Is using that #define okay, or is there a better way?

navi, 1 month ago

@lanodan me #define _XOPEN_SOURCE 500 so that nftw is visible but suddenly that breaks freebsd includes on ci bc setting a standard is supposed to hide the extensions ig

SebastienLugan, 1 month ago

@whitequark Reading this (curly braces replaced by BEGIN/END using a #define), I can't help but remember this awesome comment in fdisk.c 😄
https://github.com/microsoft/MS-DOS/blob/2d04cacc5322951f187bb17e017c12920ac8ebe2/v4.0/src/CMD/FDISK/FDISK.C#L51

shanselman, 1 month ago

@felsqualle @starfrost ya that #define was hilarious to find

freevolt24, 1 month ago

@nixCraft #define 💀 abort()

KaitlynEthylia, 1 month ago

@ielenia @MikeHar94962844 @LianSirenia Well this one should be pretty cursed

#include <stdio.h>

<a class="hashtag" data-tag="define" href="https://akko.wtf/tag/define" rel="tag ugc">#define</a> MSG "Lian is cuten"

int count() {
  static int c = 0;
  c++;
  return c % sizeof MSG;
}

int main() {
  char* msg = MSG;
  for(;count();msg++)
    putc(*msg, stdout);
  return main();
}