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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Even more problems with lcc-win
Date: Wed, 29 Mar 2017 12:22:04 -0700
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mertesthomas@gmail.com writes:
[...]
>   - Tcc: Compiles, but integer divisions with maximum values
>          are not correct (see tcc_err2.c).
[...]
> ========== begin tcc_err2.c ==========
> #include "stdio.h"
>
> #if ULONG_MAX > 4294967295U
> typedef long intType;
> #define INT_SUFFIX(num) num ## L
> #define SUFFIX "L"
> #define INTTYPE_FORMAT "l"
> #define MESSAGE "Using long.\n"
> #else
> typedef long long intType;
> #define INT_SUFFIX(num) num ## LL
> #define SUFFIX "LL"
> #define INTTYPE_FORMAT "ll"
> #define MESSAGE "Using long long.\n"
> #endif
>
> #define F_D(width) "%" #width INTTYPE_FORMAT "d"
>
> #if 0
> /* Allow the compiler to compute the division. */
> #define intExpr(num)  (num)
> #else
> /* The division will (probably) be done at runtime. */
> intType intExpr (intType number)  { return number; }
> #endif
>
>
> int main (int argc, char **argv)
> {
>   printf("sizeof(long): %lu\n", sizeof(long));
>   printf("sizeof(long long): %lu\n", sizeof(long long));
>   printf(MESSAGE);
>   printf("-9223372036854775808" SUFFIX " / -2147483649" SUFFIX " = " F_D(20) " expected:  4294967294\n",
>          intExpr(INT_SUFFIX(-9223372036854775807)-1) / INT_SUFFIX(-2147483649));
>   printf("-9223372036854775808" SUFFIX " / -2147483648" SUFFIX " = " F_D(20) " expected:  4294967296\n",
>          intExpr(INT_SUFFIX(-9223372036854775807)-1) / INT_SUFFIX(-2147483648));
>   printf(" 9223372036854775807" SUFFIX " / -2147483649" SUFFIX " = " F_D(20) " expected: -4294967294\n",
>          intExpr(INT_SUFFIX( 9223372036854775807))    / INT_SUFFIX(-2147483649));
>   printf(" 9223372036854775807" SUFFIX " / -2147483648" SUFFIX " = " F_D(20) " expected: -4294967295\n",
>          intExpr(INT_SUFFIX( 9223372036854775807))    / INT_SUFFIX(-2147483648));
>   printf("-9223372036854775808" SUFFIX " %% -2147483649" SUFFIX " = " F_D(20) " expected:          -2\n",
>          intExpr(INT_SUFFIX(-9223372036854775807)-1) % INT_SUFFIX(-2147483649));
>   printf("-9223372036854775808" SUFFIX " %% -2147483648" SUFFIX " = " F_D(20) " expected:           0\n",
>          intExpr(INT_SUFFIX(-9223372036854775807)-1) % INT_SUFFIX(-2147483648));
>   printf(" 9223372036854775807" SUFFIX " %% -2147483649" SUFFIX " = " F_D(20) " expected:           1\n",
>          intExpr(INT_SUFFIX( 9223372036854775807))    % INT_SUFFIX(-2147483649));
>   printf(" 9223372036854775807" SUFFIX " %% -2147483648" SUFFIX " = " F_D(20) " expected:  2147483647\n",
>          intExpr(INT_SUFFIX( 9223372036854775807))    % INT_SUFFIX(-2147483648));
>   return 0;
> }
> ========== end tcc_err2.c ==========

I compiled and ran your program using tcc, and it appeared to pass.
I'm using tcc 0.9.26 on x86_64 Linux (Ubuntu 16.10).

It would be handy if it would explicitly report an error if a value
doesn't match.  Also, the correct format for size_t is "%zu", not
"%lu".

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"