Another strict-alias puzzle with (unsigned) char ptrs

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Another strict-alias puzzle with (unsigned) cha...
\ Adam Dickmeiss (26 Sep 2006)
. \ Ian Lance Taylor (27 Sep 2006)

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Subject:	Another strict-alias puzzle with (unsigned) char ptrs
Group:	Gcc-help
From:	Adam Dickmeiss
Date:	26 Sep 2006

The program below prints 1 or 0 depending on GCC version and
-O2/-fstrict-aliasing being present or not. With proper optimizations
enabled, 0 is printed. Otherwise, 1 is printed.

So just to understand: strict aliases also take effect for
signed/unsigned char pointers?
/ Adam

#include <stdio.h>

static void decode_ptr(const unsigned char **src)
{
(*src)++;
}

int main(int argc, char **argv)
{
const char *src0 = "";
const char *src = src0;

decode_ptr(&src);
printf("sz = %lld\n", (long long)(src - src0));
}