drivers/char/hfmodem/refclock.c fails to compile with "gcc version 2.95.2
20000220 (Debian GNU/Linux)", but compiles normally with "gcc version
2.7.2.3". GNU assembler 2.9.5 was used in both cases. Here is the error
message:
refclock.c: In function `hfmodem_refclock_current':
refclock.c:136: Invalid `asm' statement:
refclock.c:136: fixed or forbidden register 0 (ax) was spilled for class AREG.
Here is the offending line:
__asm__("mull %2" : "=d" (tmp2), "=a" (tmp4) : "m" (scale_rdtsc), "1" (tmp0) : "ax");
It appears that above code declares register eax as output and globbered
register simultaneously. My gcc docs say: "You may not write a clobber
description in a way that overlaps with an input or output operand." Below
is a patch against 2.2.19pre16 to fix this. Please consider applying.
Regards,
Jari Ruusu <[email protected]>
--- linux-2.2.19pre16/drivers/char/hfmodem/refclock.c Tue Jan 4 20:12:14 2000
+++ linux/drivers/char/hfmodem/refclock.c Fri Mar 9 17:59:31 2001
@@ -133,7 +133,7 @@
"subl %2,%%eax\n\t"
"sbbl %3,%%edx\n\t" : "=&a" (tmp0), "=&d" (tmp1)
: "m" (dev->clk.starttime_lo), "m" (dev->clk.starttime_hi));
- __asm__("mull %2" : "=d" (tmp2), "=a" (tmp4) : "m" (scale_rdtsc), "1" (tmp0) : "ax");
+ __asm__("mull %2" : "=d" (tmp2), "=a" (tmp4) : "m" (scale_rdtsc), "1" (tmp0));
__asm__("mull %1" : "=a" (tmp3) : "m" (scale_rdtsc), "a" (tmp1) : "dx");
curtime = tmp2 + tmp3;
goto time_known;