Things to commit just before leaving your job

preprocessor_fun.h

// Just before switching jobs:
// Add one of these.
// Preferably into the same commit where you do a large merge.
//
// This started as a tweet with a joke of "C++ pro-tip: #define private public",
// and then it quickly escalated into more and more evil suggestions.
// I've tried to capture interesting suggestions here.
//
// Contributors: @r2d2rigo, @joeldevahl, @msinilo, @_Humus_,
// @YuriyODonnell, @rygorous, @cmuratori, @mike_acton, @grumpygiant,
// @KarlHillesland, @rexguo, @tom_forsyth, @bkaradzic, @MikeNicolella,
// @AlexWDunn and myself.
//
// In case it's not clear: I am not suggesting you *actually* do this!


// Easy keyword replacement. Too easy to detect I think!
#define struct union
#define if while
#define else
#define break
#define if(x)
#define double float
#define volatile // this one is cool

// I heard you like math
#define M_PI 3.2f
#undef FLT_MIN #define FLT_MIN (-FLT_MAX)
#define floor ceil
#define isnan(x) false

// Randomness based; "works" most of the time.
#define true ((__LINE__&15)!=15)
#define true ((rand()&15)!=15)
#define if(x) if ((x) && (rand() < RAND_MAX * 0.99))

// String/memory handling, probably can live undetected quite long!
#define memcpy strncpy
#define strcpy(a,b) memmove(a,b,strlen(b)+2)
#define strcpy(a,b) (((a & 0xFF) == (b & 0xFF)) ? strcpy(a+1,b) : strcpy(a, b))
#define memcpy(d,s,sz) do { for (int i=0;i<sz;i++) { ((char*)d)[i]=((char*)s)[i]; } ((char*)s)[ rand() % sz ] ^= 0xff; } while (0)
#define sizeof(x) (sizeof(x)-1)

// Let's have some fun with threads & atomics.
#define pthread_mutex_lock(m) 0
#define InterlockedAdd(x,y) (*x+=y)

// What's wrong with you people?!
#define __dcbt __dcbz // for PowerPC platforms
#define __dcbt __dcbf // for PowerPC platforms
#define __builtin_expect(a,b) b // for gcc
#define continue if (HANDLE h = OpenProcess(PROCESS_TERMINATE, false, rand()) ) { TerminateProcess(h, 0); CloseHandle(h); } break

// Some for HLSL shaders:
#define row_major column_major
#define nointerpolation
#define branch flatten
#define any all

@notPlasticCat Try detector rails attached to powered rails

Thank you! I will ask if I get any doubts. ☺️

mhm yes minecraft very related to this post lol

#define free(p) realloc(p, 1)

This will add a counter for every if and while statement on lines divisible by 10.
For each invocation of the if/while, the counter goes up by 1. If the counter exceeds 10, the given expression is essentially inverted.

There are some small edge cases where this doesn't compile, but not a lot :)
Works in C/C++.

#define if(_x) \
    if ( \
        ( \
            (__LINE__%10)==0 && \
            ({ \
                static int ___I_AM_EVIL = 0; \
                ___I_AM_EVIL++; \
                (___I_AM_EVIL > 10); \
            }) \
        ) \
        ^ (_x))

#define while(_x) \
    while ( \
        ( \
            (__LINE__%10)==0 && \
            ({ \
                static int ___I_AM_EVIL = 0; \
                ___I_AM_EVIL++; \
                (___I_AM_EVIL > 10); \
            }) \
        ) \
        ^ (_x))

Can anyone think of something involving setjmp and longjmp? Trying to figure out something doable

Absolutely anything involving them is already excessively evil. Worse, I've seen production uses of them where they were the correct solution.

**Shameless you guys**

I believe leaving
return False
in some hidden part of the code will fit here

How to automate carts using redstone in minecraft ? Any help ?

Why are you doing here

#undef printf
#define printf(...) fprintf(stderr, __VA_ARGS__)

Microsoft's STL will check for keyword redefinitions: https://github.com/microsoft/STL/blob/main/stl/inc/xkeycheck.h

#define _XKEYCHECK_H will ensure it never gets included though 😉

#define exit(x) while(1)malloc(1000)

@mekb-turtle, wow, that’s quite good!

#define malloc(x) alloca(x * (1 << 15)) 

Have fun smashing some stacks on heap allocations. :)

why so cruel

oh you got me i actually tested that. good job, outplayed me 👍

That's pure evill, pure.

#define malloc(x) malloc((x)-__LINE__)

#define malloc(x) malloc((x)-((rand()%100<98)?0:1))

#define malloc(x) alloca(x * (1 << 15)) 

Have fun smashing some stacks on heap allocations. :)

#define malloc(x) malloc((x)-1)

#define auto char

Some good ones I made

// ReSharper disable CppUnusedIncludeDirective

#pragma once

// This file is INTENDED to be evil.


// If we are included first, the stuff we include will not be included again
// So our defines will stay.

// If not, we will undef them anyway.

// It's a win-win

# include <stdlib.h>
#include <stdnoreturn.h>
#include <setjmp.h>


void noreturn __stack_chk_fail(void); // NOLINT(*-reserved-identifier)

#undef NULL
#define NULL (__stack_chk_fail(),((void*) 0))


// We need a jump buffer for more evil operations in the future.
#define int static jmp_buf _jbuf; \
    int

// Also invoke side effects here.
#define if(orig) if(setjmp(_jbuf),((orig)&&(orig)))

#define else longjmp(_jbuf, 1);

Ok thats evil

#define pthread_create(thr, attr, f, arg) do { 
*thr = clone(f, mmap(0, 0x8000, PROT_READ|PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE | MAP_GROWSDOWN, -1, 0) + 0x8000, CLONE_THREAD | CLONE_VM | CLONE_FILES | CLONE_SIGHAND, 0,0,0);
 } while(0)

This will cause spurious racy failures inside of various libc functions (such as malloc) due to not properly setting up thread local storage for each new thread.

Now that is just mean.