[bug report] cmd: mbr: Allow 4 MBR partitions without need for extended

[Nam Cao]

On Mon, 29 Jan 2024 18:18:03 +0300 Dan Carpenter wrote:
> Hello Alexander Gendin,
> 
> The patch 04291ee0aba6: "cmd: mbr: Allow 4 MBR partitions without
> need for extended" from Oct 9, 2023, leads to the following Smatch
> static checker warning:
> 
> 	test/cmd/mbr.c:243 mbr_test_run()
> 	warn: sizeof(NUMBER)?
> 
> test/cmd/mbr.c
>     233         ulong mbr_wa, ebr_wa, ra, ebr_blk, mbr_parts_max;
>     234         struct udevice *dev;
>     235         ofnode root, node;
>     236 
>     237         /* Enable the mmc6 node for this test */
>     238         root = oftree_root(oftree_default());
>     239         node = ofnode_find_subnode(root, "mmc6");
>     240         ut_assert(ofnode_valid(node));
>     241         ut_assertok(lists_bind_fdt(gd->dm_root, node, &dev, NULL, false));
>     242 
> --> 243         mbr_parts_max = sizeof('\0') + 2 +  
>                                        ^^^
> You probably wanted this to a readable way to explain that we are
> leaving space for the NUL char, however this size is 4 not 1.  (I guess
> this is from type promotion?)

Quick google search told me:
"Perhaps surprisingly, character constants in C are of type int, so
sizeof('a') is sizeof(int) (though this is another area where C++
differs)" [1].

Quite interesting, TIL.

Best regards,
Nam

[1] https://c-faq.com/charstring/sizeofchar.html