Affected subclause: [lex.pptoken]
Rationale: Required for new features
. Effect on original feature: Valid C++ 2003 code may fail to compile or produce different results in
this revision of C++
. Specifically, macros named
R,
u8,
u8R,
u,
uR,
U,
UR, or
LR will
not be expanded when adjacent to a
string-literal but will be interpreted as
part of the
string-literal.[
Example 1:
#define u8 "abc"
const char* s = u8"def";
—
end example]
Affected subclause: [lex.pptoken]
Change: User-defined literal string support
. Rationale: Required for new features
. Effect on original feature: Valid C++ 2003 code may fail to compile or produce different results in
this revision of C++
. [
Example 2:
#define _x "there"
"hello"_x
Previously, #1 would have consisted of two separate preprocessing tokens and
the macro
_x would have been expanded
.In this revision of C++,
#1 consists of a single preprocessing token, so the macro is not expanded
. —
end example]
Affected subclause: [lex.key]
Rationale: Required for new features
. Effect on original feature: Added to Table
5, the following identifiers are new keywords:
alignas,
alignof,
char16_t,
char32_t,
constexpr,
decltype,
noexcept,
nullptr,
static_assert,
and
thread_local. Valid C++ 2003 code using these identifiers is invalid in this revision of C++
. Affected subclause: [lex.icon]
Change: Type of integer literals
. Rationale: C99 compatibility
. Effect on original feature: Certain integer literals larger than can be represented by
long could
change from an unsigned integer type to
signed long.