| Message ID | 1355406304.19560.39.camel@shinybook.infradead.org (mailing list archive) |
|---|---|
| State | Rejected, archived |
| Headers | show |
On Thu, Dec 13, 2012 at 01:45:04PM +0000, David Woodhouse wrote: > Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> > --- > I'm about to make the kernel use these: > http://git.infradead.org/users/dwmw2/byteswap.git > > lib.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/lib.c b/lib.c > index 396e9f1..d747a3e 100644 > --- a/lib.c > +++ b/lib.c > @@ -698,6 +698,11 @@ void declare_builtin_functions(void) > add_pre_buffer("extern int __builtin_popcountl(unsigned long);\n"); > add_pre_buffer("extern int __builtin_popcountll(unsigned long long);\n"); > > + /* And byte-swapping operations.. */ > + add_pre_buffer("extern short __builtin_bswap16(short);\n"); > + add_pre_buffer("extern int __builtin_bswap32(int);\n"); > + add_pre_buffer("extern long long __builtin_bswap64(long long);\n"); GCC defines these to use int16_t, int32_t, and int64_t, respectively. The first two of those should match up to "short" and "int" without any issue, but on 64-bit platforms, stdint.h defines int64_t as "long", not "long long". That could lead to some type incompatibilities. - Josh Triplett -- To unsubscribe from this list: send the line "unsubscribe linux-sparse" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 2012-12-13 at 08:11 -0800, Josh Triplett wrote: > > GCC defines these to use int16_t, int32_t, and int64_t, respectively. > The first two of those should match up to "short" and "int" without any > issue, but on 64-bit platforms, stdint.h defines int64_t as "long", not > "long long". That could lead to some type incompatibilities. Are we allowed to use int64_t? Or must we pretend that it's still the 20th century and stdint.h might not be present?
diff --git a/lib.c b/lib.c index 396e9f1..d747a3e 100644 --- a/lib.c +++ b/lib.c @@ -698,6 +698,11 @@ void declare_builtin_functions(void) add_pre_buffer("extern int __builtin_popcountl(unsigned long);\n"); add_pre_buffer("extern int __builtin_popcountll(unsigned long long);\n"); + /* And byte-swapping operations.. */ + add_pre_buffer("extern short __builtin_bswap16(short);\n"); + add_pre_buffer("extern int __builtin_bswap32(int);\n"); + add_pre_buffer("extern long long __builtin_bswap64(long long);\n"); + /* And some random ones.. */ add_pre_buffer("extern void *__builtin_return_address(unsigned int);\n"); add_pre_buffer("extern void *__builtin_extract_return_addr(void *);\n");
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> --- I'm about to make the kernel use these: http://git.infradead.org/users/dwmw2/byteswap.git lib.c | 5 +++++ 1 file changed, 5 insertions(+)