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PATCH, rs6000: silence warnings
- From: Ben Elliston <bje at au1 dot ibm dot com>
- To: gcc-patches at gcc dot gnu dot org
- Cc: dje dot gcc at gmail dot com
- Date: Tue, 21 Apr 2009 11:48:44 +1000
- Subject: PATCH, rs6000: silence warnings
When building libgcc on powerpc64-linux, I see:
/home/bje/source/gcc-trunk/libgcc/../gcc/config/rs6000/linux-unwind.h:98: warning: cast discards qualifiers from pointer target type
/home/bje/source/gcc-trunk/libgcc/../gcc/config/rs6000/linux-unwind.h:99: warning: cast discards qualifiers from pointer target type
/home/bje/source/gcc-trunk/libgcc/../gcc/config/rs6000/linux-unwind.h:101: warning: cast discards qualifiers from pointer target type
/home/bje/source/gcc-trunk/libgcc/../gcc/config/rs6000/linux-unwind.h:110: warning: cast discards qualifiers from pointer target type
/home/bje/source/gcc-trunk/libgcc/../gcc/config/rs6000/linux-unwind.h:120: warning: cast discards qualifiers from pointer target type
This patch cleans up these casts by eliminating them altogether. With
this change, the code becomes more typesafe and easier to read. OK for
mainline? (Regression test and bootstrap underway on power64-linux).
Thanks,
Ben
2009-04-21 Ben Elliston <bje@au.ibm.com>
* config/rs6000/linux-unwind.h (get_regs): Remove type
puns. Change the type of `pc' to an array of unsigned ints and
update all users. Constify frame24.
Index: /home/bje/source/gcc-trunk/gcc/config/rs6000/linux-unwind.h
===================================================================
--- /home/bje/source/gcc-trunk/gcc/config/rs6000/linux-unwind.h (revision 146466)
+++ /home/bje/source/gcc-trunk/gcc/config/rs6000/linux-unwind.h (working copy)
@@ -91,14 +91,13 @@
static struct gcc_regs *
get_regs (struct _Unwind_Context *context)
{
- const unsigned char *pc = context->ra;
+ const unsigned int *pc = context->ra;
/* addi r1, r1, 128; li r0, 0x0077; sc (sigreturn) */
/* addi r1, r1, 128; li r0, 0x00AC; sc (rt_sigreturn) */
- if (*(unsigned int *) (pc + 0) != 0x38210000 + SIGNAL_FRAMESIZE
- || *(unsigned int *) (pc + 8) != 0x44000002)
+ if (pc[0] != 0x38210000 + SIGNAL_FRAMESIZE || pc[2] != 0x44000002)
return NULL;
- if (*(unsigned int *) (pc + 4) == 0x38000077)
+ if (pc[1] == 0x38000077)
{
struct sigframe {
char gap[SIGNAL_FRAMESIZE];
@@ -107,17 +106,17 @@
} *frame = (struct sigframe *) context->cfa;
return frame->regs;
}
- else if (*(unsigned int *) (pc + 4) == 0x380000AC)
+ else if (pc[1] == 0x380000AC)
{
/* This works for 2.4 kernels, but not for 2.6 kernels with vdso
because pc isn't pointing into the stack. Can be removed when
no one is running 2.4.19 or 2.4.20, the first two ppc64
kernels released. */
- struct rt_sigframe_24 {
+ const struct rt_sigframe_24 {
int tramp[6];
void *pinfo;
struct gcc_ucontext *puc;
- } *frame24 = (struct rt_sigframe_24 *) pc;
+ } *frame24 = (const struct rt_sigframe_24 *) context->ra;
/* Test for magic value in *puc of vdso. */
if ((long) frame24->puc != -21 * 8)
@@ -146,16 +145,15 @@
static struct gcc_regs *
get_regs (struct _Unwind_Context *context)
{
- const unsigned char *pc = context->ra;
+ const unsigned int *pc = context->ra;
/* li r0, 0x7777; sc (sigreturn old) */
/* li r0, 0x0077; sc (sigreturn new) */
/* li r0, 0x6666; sc (rt_sigreturn old) */
/* li r0, 0x00AC; sc (rt_sigreturn new) */
- if (*(const unsigned int *) (pc + 4) != 0x44000002)
+ if (pc[1] != 0x44000002)
return NULL;
- if (*(const unsigned int *) (pc + 0) == 0x38007777
- || *(const unsigned int *) (pc + 0) == 0x38000077)
+ if (pc[0] == 0x38007777 || pc[0] == 0x38000077)
{
struct sigframe {
char gap[SIGNAL_FRAMESIZE];
@@ -164,8 +162,7 @@
} *frame = (struct sigframe *) context->cfa;
return frame->regs;
}
- else if (*(const unsigned int *) (pc + 0) == 0x38006666
- || *(const unsigned int *) (pc + 0) == 0x380000AC)
+ else if (pc[0] == 0x38006666 || pc[0] == 0x380000AC)
{
struct rt_sigframe {
char gap[SIGNAL_FRAMESIZE + 16];