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isn't an array a contiguous region of memory?

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For this question, keep in mind that I'm running MSYS2.  (I don't know if
it is relevant at all, though.)

My idea of an array is a contiguous region of memory.  But I was totally
surprised what I saw today and I can't make any sense of this.  Here's
what I did.  I wrote the program below, which produced the executable
argv.exe.  I renamed it to a.exe and ran it as ``./a.exe a bc d''.  I'm
very surprised by the memory location 6446082752 being an integer
greater than 6446078248.  As you can see in the source code, the first
number is &argv[0] and the second is &argv[1].  In my mind, the latter
should be *always* greater than the former.

--8<---------------cut here---------------start------------->8---
%./a.exe a bc d
we have 4 arguments
argv[0] = ./a
argv[1] = a
argv[2] = bc
argv[3] = d
6446082752 -> . = 46
6446078248 -> a = 97
--8<---------------cut here---------------end--------------->8---

I need to explain a detail about this output.  In MSYS2, even though the
shell prepares the argv of a.exe with argv[0] = "./a.exe", we really
only see "./a" in the output.  I tried the program off of MSYS2 --- that
is, compiling running it through cmd.exe, that is, without msys-2.0.dll
--- and this effect does not happen.  I'm saying this because maybe
msys-2.0.dll has something to do with this.  If that's the case,
nevermind the question --- I'd go and ask in some MinGW group, wherever
it may be.

(*) Source code

#include <stdio.h>

int main(int argc, char *argv[]) {
  printf("we have %d arguments\n", argc);

  for (int i = 0; i < argc; ++i) 
    printf("argv[%d] = %s\n", i, argv[i]);

  printf("%lu -> %c = %d\n", 
     (unsigned long) &argv[0], argv[0][0], argv[0][0]);
  printf("%lu -> %c = %d\n", 
     (unsigned long) &argv[1], argv[1][0], argv[1][0]);
  return 0;
}

%make argv
gcc -Wall -x c -g -std=c99 -pedantic-errors    argv.c   -o argv

%mv argv.exe a.exe
%

I think the renaming has nothing to do with the question.  I'm only
showing that because that's what I did when I got the strange output
above.

I can't seem to reproduce that situation.

When I run it right now, for instance, I see the sensible output:

%./a.exe a bc d
we have 4 arguments
argv[0] = ./a
argv[1] = a
argv[2] = bc
argv[3] = d
4294954096 -> . = 46
4294954104 -> a = 97
%

It was counting bytes here that I conjectured that mysys-2.0.dll must be
erasing the ".exe" off of "./a.exe" because you can see that &argv[0] is
at 4294954096 but &argv[1] is at 4294954104.

I'll appreciate any insights you might have.  Thank you!

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Thread

isn't an array a contiguous region of memory? Meredith Montgomery <mmontgomery@levado.to> - 2021-12-21 16:41 -0300
  Re: isn't an array a contiguous region of memory? scott@slp53.sl.home (Scott Lurndal) - 2021-12-21 20:10 +0000
    Re: isn't an array a contiguous region of memory? scott@slp53.sl.home (Scott Lurndal) - 2021-12-21 20:13 +0000
  Re: isn't an array a contiguous region of memory? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2021-12-21 20:19 +0000
    Re: isn't an array a contiguous region of memory? Meredith Montgomery <mmontgomery@levado.to> - 2021-12-21 21:43 -0300
  Re: isn't an array a contiguous region of memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-12-21 12:22 -0800
    Re: isn't an array a contiguous region of memory? Meredith Montgomery <mmontgomery@levado.to> - 2021-12-21 21:48 -0300
  Re: isn't an array a contiguous region of memory? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2021-12-22 16:38 -0800
    Irreproducible results (Was: isn't an array a contiguous region of memory?) gazelle@shell.xmission.com (Kenny McCormack) - 2021-12-23 12:46 +0000
      Re: Irreproducible results Meredith Montgomery <mmontgomery@levado.to> - 2021-12-25 21:57 -0300

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