c/2394: -O2 -mcpu=ultrasparc can generate std's to non-8-byte aligned stack offsets

c/2394: -O2 -mcpu=ultrasparc can generate std's to non-8-byte aligned stack offsets

[grubba]

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>Number:         2394
>Category:       c
>Synopsis:       -O2 -mcpu=ultrasparc can generate std's to non-8-byte aligned stack offsets
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Mar 26 10:36:01 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Henrik Grubbström <grubba@roxen.com>
>Release:        gcc version 2.95.2 19991024 (release)
>Organization:
>Environment:
$ uname -svrmip
SunOS 5.8 Generic_108528-04 sun4u sparc SUNW,Ultra-80
>Description:
Compilation of the attached file generates the following code:

...
.stabn 68,0,86,.LLM74-gccbug
.LLM74:
.LLBE7:
	mov	%l1, %o1
	mov	%l0, %o0
	std	%f2, [%sp+92]
	mov	%l2, %o2
	mov	%l3, %o3
	st	%i1, [%sp+100]
	mov	%l4, %o4
	call	gccbug_1, 0
	mov	0, %o5
...

Note the std %f2, [%sp+92]. 92 (0x5c) is not a multiple of 8,
the std will thus cause a SIGBUS.
>How-To-Repeat:
Compile the attached file with
$ gcc -g -mcpu=ultrasparc -O2 -S gccbug.c -o gccbug.s
Search for the code following the stab for line 86.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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