This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
optimization/8916: unsigned char assign gets hosed.
- From: jcphillips at yahoo dot com
- To: gcc-gnats at gcc dot gnu dot org
- Date: 12 Dec 2002 16:48:00 -0000
- Subject: optimization/8916: unsigned char assign gets hosed.
- Reply-to: jcphillips at yahoo dot com
>Number: 8916
>Category: optimization
>Synopsis: unsigned char assign gets hosed.
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: unassigned
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Thu Dec 12 08:56:02 PST 2002
>Closed-Date:
>Last-Modified:
>Originator: jcphillips@yahoo.com
>Release: gcc v3.2
>Organization:
>Environment:
cygwin. gcc built for mcore-elf.
>Description:
The following source fails to generate correct asm:
----------------
extern void ExtFunc(char *c);
void test()
{
unsigned char data = 166;
ExtFunc(&data);
}
--------------------------
mcore-elf-objdump output is:
--------------------------
test.o: file format elf32-mcore-big
Disassembly of section .text:
00000000 <test>:
0: 24f0 subi r0, 16
2: 9f20 st r15, (r0, 8)
4: 2c07 bmaski r7, 0
6: b700 stb r7, (r0, 0)
8: 1202 mov r2, r0
a: 7f02 jsri 0x0 // from address pool at 0x14
c: 8f20 ld r15, (r0, 8)
e: 20f0 addi r0, 16
10: 00cf jmp r15
12: 0000 bkpt
14: 0000 bkpt
...
--------------------------
The bmaski r7,0 causes the char value to be 0xFF.
When compiled without optimization, result is fine.
>How-To-Repeat:
compile with:
mcore-elf-gcc -c -O2 -mbig-endian -m210 test.c
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted: