Hi!
Apparently there is a -Wsign-compare warning if ptrdiff_t has precision of
int, then (t - s + 1 + 2) / 3 * 4 has int type while cnt unsigned int.
This doesn't warn if ptrdiff_t has larger precision, say on x86_64
it is 64-bit and so (t - s + 1 + 2) / 3 * 4 has long type and cnt unsigned
int. And it doesn't warn when using older binutils (in my tests I've
used new binutils on x86_64 and old binutils on i686).
Anyway, earlier condition guarantees that t - s is at most 256-ish and
t >= s by construction, so we can just cast it to (unsigned) to avoid
the warning.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2024-07-17 Jakub Jelinek <ja...@redhat.com>
PR other/115958
* varasm.cc (default_elf_asm_output_ascii): Cast t - s to unsigned
to avoid -Wsign-compare warnings.
--- gcc/varasm.cc.jj 2024-07-16 19:33:53.553501415 +0200
+++ gcc/varasm.cc 2024-07-16 22:35:05.132495049 +0200
@@ -8558,7 +8558,7 @@ default_elf_asm_output_ascii (FILE *f, c
{
if (t == p && t != s)
{
- if (cnt <= (t - s + 1 + 2) / 3 * 4
+ if (cnt <= ((unsigned) (t - s) + 1 + 2) / 3 * 4
&& (!prev_base64 || (t - s) >= 16)
&& ((t - s) > 1 || cnt <= 2))
{
@@ -8584,7 +8584,7 @@ default_elf_asm_output_ascii (FILE *f, c
break;
}
}
- if (cnt > (t - s + 2) / 3 * 4 && (t - s) >= 3)
+ if (cnt > ((unsigned) (t - s) + 2) / 3 * 4 && (t - s) >= 3)
{
if (bytes_in_chunk > 0)
{
Jakub
