Improve diagnostics for UCNs referring to control characters and members of the
basic source character set in C++98. Add -Wc++98-compat diagnostics for same in
literals in C++11. Extend such support to cover string literals as well as
character literals, and mark N2170 as done.
This seems too minor to warrant a release note to me. Let me know if you disagree.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@152444 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/LiteralSupport.cpp b/lib/Lex/LiteralSupport.cpp
index e0a5ba3..ae8157d 100644
--- a/lib/Lex/LiteralSupport.cpp
+++ b/lib/Lex/LiteralSupport.cpp
@@ -179,7 +179,8 @@
/// ProcessUCNEscape - Read the Universal Character Name, check constraints and
/// return the UTF32.
-static bool ProcessUCNEscape(const char *&ThisTokBuf, const char *ThisTokEnd,
+static bool ProcessUCNEscape(const char *ThisTokBegin, const char *&ThisTokBuf,
+ const char *ThisTokEnd,
uint32_t &UcnVal, unsigned short &UcnLen,
FullSourceLoc Loc, DiagnosticsEngine *Diags,
const LangOptions &Features,
@@ -187,8 +188,7 @@
if (!Features.CPlusPlus && !Features.C99 && Diags)
Diags->Report(Loc, diag::warn_ucn_not_valid_in_c89);
- // Save the beginning of the string (for error diagnostics).
- const char *ThisTokBegin = ThisTokBuf;
+ const char *UcnBegin = ThisTokBuf;
// Skip the '\u' char's.
ThisTokBuf += 2;
@@ -210,31 +210,43 @@
if (UcnLenSave) {
if (Diags) {
SourceLocation L =
- Lexer::AdvanceToTokenCharacter(Loc, ThisTokBuf-ThisTokBegin,
+ Lexer::AdvanceToTokenCharacter(Loc, UcnBegin - ThisTokBegin,
Loc.getManager(), Features);
- Diags->Report(FullSourceLoc(L, Loc.getManager()),
- diag::err_ucn_escape_incomplete);
+ Diags->Report(L, diag::err_ucn_escape_incomplete);
}
return false;
}
+
// Check UCN constraints (C99 6.4.3p2) [C++11 lex.charset p2]
- bool invalid_ucn = (0xD800<=UcnVal && UcnVal<=0xDFFF) // surrogate codepoints
- || 0x10FFFF < UcnVal; // maximum legal UTF32 value
-
- // C++11 allows UCNs that refer to control characters and basic source
- // characters inside character and string literals
- if (!Features.CPlusPlus0x || !in_char_string_literal) {
- if ((UcnVal < 0xa0 &&
- (UcnVal != 0x24 && UcnVal != 0x40 && UcnVal != 0x60 ))) { // $, @, `
- invalid_ucn = true;
- }
- }
-
- if (invalid_ucn) {
+ if ((0xD800 <= UcnVal && UcnVal <= 0xDFFF) || // surrogate codepoints
+ UcnVal > 0x10FFFF) { // maximum legal UTF32 value
if (Diags)
Diags->Report(Loc, diag::err_ucn_escape_invalid);
return false;
}
+
+ // C++11 allows UCNs that refer to control characters and basic source
+ // characters inside character and string literals
+ if (UcnVal < 0xa0 &&
+ (UcnVal != 0x24 && UcnVal != 0x40 && UcnVal != 0x60)) { // $, @, `
+ bool IsError = (!Features.CPlusPlus0x || !in_char_string_literal);
+ if (Diags) {
+ SourceLocation UcnBeginLoc =
+ Lexer::AdvanceToTokenCharacter(Loc, UcnBegin - ThisTokBegin,
+ Loc.getManager(), Features);
+ char BasicSCSChar = UcnVal;
+ if (UcnVal >= 0x20 && UcnVal < 0x7f)
+ Diags->Report(UcnBeginLoc, IsError ? diag::err_ucn_escape_basic_scs :
+ diag::warn_cxx98_compat_literal_ucn_escape_basic_scs)
+ << StringRef(&BasicSCSChar, 1);
+ else
+ Diags->Report(UcnBeginLoc, IsError ? diag::err_ucn_control_character :
+ diag::warn_cxx98_compat_literal_ucn_control_character);
+ }
+ if (IsError)
+ return false;
+ }
+
return true;
}
@@ -242,7 +254,8 @@
/// convert the UTF32 to UTF8 or UTF16. This is a subroutine of
/// StringLiteralParser. When we decide to implement UCN's for identifiers,
/// we will likely rework our support for UCN's.
-static void EncodeUCNEscape(const char *&ThisTokBuf, const char *ThisTokEnd,
+static void EncodeUCNEscape(const char *ThisTokBegin, const char *&ThisTokBuf,
+ const char *ThisTokEnd,
char *&ResultBuf, bool &HadError,
FullSourceLoc Loc, unsigned CharByteWidth,
DiagnosticsEngine *Diags,
@@ -250,8 +263,8 @@
typedef uint32_t UTF32;
UTF32 UcnVal = 0;
unsigned short UcnLen = 0;
- if (!ProcessUCNEscape(ThisTokBuf, ThisTokEnd, UcnVal, UcnLen, Loc, Diags,
- Features)) {
+ if (!ProcessUCNEscape(ThisTokBegin, ThisTokBuf, ThisTokEnd, UcnVal, UcnLen,
+ Loc, Diags, Features, true)) {
HadError = 1;
return;
}
@@ -787,6 +800,8 @@
Kind = kind;
+ const char *TokBegin = begin;
+
// Skip over wide character determinant.
if (Kind != tok::char_constant) {
++begin;
@@ -803,7 +818,7 @@
--end;
} while (end[-1] != '\'');
UDSuffixBuf.assign(end, UDSuffixEnd);
- UDSuffixOffset = end - begin + 1;
+ UDSuffixOffset = end - TokBegin;
}
// Trim the ending quote.
@@ -885,7 +900,7 @@
// Is this a Universal Character Name excape?
if (begin[1] == 'u' || begin[1] == 'U') {
unsigned short UcnLen = 0;
- if (!ProcessUCNEscape(begin, end, *buffer_begin, UcnLen,
+ if (!ProcessUCNEscape(TokBegin, begin, end, *buffer_begin, UcnLen,
FullSourceLoc(Loc, PP.getSourceManager()),
&PP.getDiagnostics(), PP.getLangOptions(),
true))
@@ -1113,6 +1128,7 @@
continue;
}
+ const char *ThisTokBegin = ThisTokBuf;
const char *ThisTokEnd = ThisTokBuf+ThisTokLen;
// Remove an optional ud-suffix.
@@ -1208,8 +1224,9 @@
}
// Is this a Universal Character Name escape?
if (ThisTokBuf[1] == 'u' || ThisTokBuf[1] == 'U') {
- EncodeUCNEscape(ThisTokBuf, ThisTokEnd, ResultPtr,
- hadError, FullSourceLoc(StringToks[i].getLocation(),SM),
+ EncodeUCNEscape(ThisTokBegin, ThisTokBuf, ThisTokEnd,
+ ResultPtr, hadError,
+ FullSourceLoc(StringToks[i].getLocation(), SM),
CharByteWidth, Diags, Features);
continue;
}