I did a few simple independent tests between 'char *foo = "foo"' and 'char
foo[] = "foo"' and they confirmed what the KJ docs say, that the latter
results in a smaller object. So I did a test with <fs/partitions/check.c>.
static char *make_block_name(struct gendisk *disk)
{
- static char *block_str = "block:";
+ static char block_str[] = "block:";
<fs/partitions/check.o> goes from 8149 bytes to 8137 bytes. 'readelf'
shows that "block:" got moved from .rodata.str1.1 to .data and a
relocation token got removed that pointed into .rodata.str1.1, saving 12
bytes.
<fs/built-in.o> goes from 1337360 to 1337320, saving 40 bytes.
<vmlinux>, however, stays exactly the same, at 4520468 bytes. And
<arch/i386/boot/bzImage> actually increases from 1702520 to 1072552,
losing 32 bytes.
I could assume that the latter could be due to happenstance of data
ordering before compression, but I'm sure I'm looking at the wrong
pre-compression file. What file should I be looking at if I want the ELF
image of the kernel fully-built but before the bootsector and so forth get
added to it?
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