--- Comment #12 from sqrammi at hotmail dot com 2007-01-26 21:10 ---
This was confirmed to be a problem with alignment fixup in the kernel.
Do an 'echo 2 > /proc/cpu/alignment' and misaligned accesses are fixed up, and
this problem goes away. Misaligned accesses should IMHO not be comp
--- Comment #11 from sqrammi at hotmail dot com 2007-01-25 18:01 ---
Thinking about it some more, this actually may be a bug in my Linux kernel
configuration that fixes up unaligned accesses. It's probably trying to fix up
for a big-endian system on my little-endian system.
--
http
--- Comment #10 from sqrammi at hotmail dot com 2007-01-25 17:55 ---
Great. That's perfect.
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30581
--- Comment #8 from sqrammi at hotmail dot com 2007-01-25 17:45 ---
It would be easy to add support to the compiler to at least warn about char
arrays of non-CPU-word-size length being placed on the stack, right? It
wouldn't even have to be a warning that shows up unless -Wall (or it's
--- Comment #9 from schwab at suse dot de 2007-01-25 17:47 ---
Use -Wcast-align.
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30581
--- Comment #7 from rearnsha at gcc dot gnu dot org 2007-01-25 17:35
---
(In reply to comment #6)
> The problem is that the compiler is not either
> 1) automatically aligning the
> buffer so that the program actually works or
It doesn't have to, because the user hasn't asked it to (a
--- Comment #6 from sqrammi at hotmail dot com 2007-01-25 17:28 ---
The problem is that the compiler is not either 1) automatically aligning the
buffer so that the program actually works or 2) warning the user that their
code is retarded and needs to be modified so that all the stacks fi
--- Comment #5 from rearnsha at gcc dot gnu dot org 2007-01-25 17:25
---
--> volatile char buf[512] /*__attribute__ ((aligned (4)))*/;
WHat makes you think this buffer will be word-aligned? One of your
sub-routines creates a variable with 33 bytes, and when inlining happens
there's no
--- Comment #4 from sqrammi at hotmail dot com 2007-01-25 17:12 ---
Created an attachment (id=12956)
--> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=12956&action=view)
Modified code - no warnings
--
sqrammi at hotmail dot com changed:
What|Removed
--- Comment #3 from sqrammi at hotmail dot com 2007-01-25 17:11 ---
I've modified the source so that there are no warnings and (hopefully) no
aliasing violations. The problem still occurs. Here is my line that I use to
compile:
arm-926ejs-linux-gnu-gcc -Wall -O2 -fno-strict-aliasing g
--- Comment #2 from pinskia at gcc dot gnu dot org 2007-01-24 23:48 ---
First you are violating C aliasing rules here:
u8 d[33] = {0}, *e = (u8 *)d;
*((unsigned int *)a) = strlen(e);
And a couple other places.
What options are you running this program wit
--- Comment #1 from sqrammi at hotmail dot com 2007-01-24 23:44 ---
Created an attachment (id=12953)
--> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=12953&action=view)
Source file to produce this bug
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30581
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