Standard C++ does not include hexadecimal floating point numbers. The
preprocessor correctly pedwarns for C++ if such a preprocessing token is
converted to a token, but it incorrectly allows p+ and p- in preprocessing
tokens in standard C++ mode in the first place. The problem is probably the
table
static const struct lang_flags lang_defaults[] =
{ /* c99 c++ xnum std // digr */
/* CXX98 */ { 0, 1, 1, 1, 1, 1 },
in libcpp/init.c: xnum should be 0 not 1. The valid C++ testcases this affects
(compile with -std=c++98 -pedantic-errors, should execute OK, instead aborts)
are along the lines of gcc.dg/c90-hexfloat-2.c:
#define f (
#define l )
#define str(x) #x
#define xstr(x) str(x)
/* C90 and C++: "0x1p+( 0x1p+)"; C99: "0x1p+f 0x1p+l" */
const char *s = xstr(0x1p+f 0x1p+l);
extern "C" void abort (void);
extern "C" int strcmp (const char *, const char *);
int
main (void)
{
if (strcmp (s, "0x1p+( 0x1p+)"))
abort ();
else
return 0; /* Correct C90 and C++ behavior. */
}
--
Summary: standard C++ should not have hex float preprocessing
tokens
Product: gcc
Version: 4.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: preprocessor
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: jsm28 at gcc dot gnu dot org
CC: gcc-bugs at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23827
