[cfe-commits] r70329 - in /cfe/trunk: include/clang/Basic/DiagnosticGroups.td include/clang/Basic/DiagnosticLexKinds.td lib/Lex/LiteralSupport.cpp test/Lexer/constants.c
Chris Lattner
sabre at nondot.org
Tue Apr 28 14:51:46 PDT 2009
Author: lattner
Date: Tue Apr 28 16:51:46 2009
New Revision: 70329
URL: http://llvm.org/viewvc/llvm-project?rev=70329&view=rev
Log:
Implement -Wfour-char-constants, which is an extension, not an extwarn,
and apparently not part of -Wall
Modified:
cfe/trunk/include/clang/Basic/DiagnosticGroups.td
cfe/trunk/include/clang/Basic/DiagnosticLexKinds.td
cfe/trunk/lib/Lex/LiteralSupport.cpp
cfe/trunk/test/Lexer/constants.c
Modified: cfe/trunk/include/clang/Basic/DiagnosticGroups.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticGroups.td?rev=70329&r1=70328&r2=70329&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticGroups.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticGroups.td Tue Apr 28 16:51:46 2009
@@ -33,7 +33,7 @@
def : DiagGroup<"format-security">;
def : DiagGroup<"format=2">;
def : DiagGroup<"format">;
-def : DiagGroup<"four-char-constants">;
+def FourByteMultiChar : DiagGroup<"four-char-constants">;
def : DiagGroup<"init-self">;
Modified: cfe/trunk/include/clang/Basic/DiagnosticLexKinds.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticLexKinds.td?rev=70329&r1=70328&r2=70329&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticLexKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticLexKinds.td Tue Apr 28 16:51:46 2009
@@ -53,6 +53,9 @@
"invalid argument to convert to character">;
def ext_multichar_character_literal : ExtWarn<
"multi-character character constant">, InGroup<MultiChar>;
+def ext_four_char_character_literal : Extension<
+ "multi-character character constant">, InGroup<FourByteMultiChar>;
+
// Literal
def ext_nonstandard_escape : Extension<
Modified: cfe/trunk/lib/Lex/LiteralSupport.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Lex/LiteralSupport.cpp?rev=70329&r1=70328&r2=70329&view=diff
==============================================================================
--- cfe/trunk/lib/Lex/LiteralSupport.cpp (original)
+++ cfe/trunk/lib/Lex/LiteralSupport.cpp Tue Apr 28 16:51:46 2009
@@ -631,19 +631,19 @@
// FIXME: The "Value" is an uint64_t so we can handle char literals of
// upto 64-bits.
- assert(PP.getTargetInfo().getIntWidth() <= 64 &&
- "Assumes sizeof(int) on target is <= 64");
- assert(PP.getTargetInfo().getWCharWidth() <= 64 &&
- "Assumes sizeof(wchar) on target is <= 64");
// FIXME: This extensively assumes that 'char' is 8-bits.
assert(PP.getTargetInfo().getCharWidth() == 8 &&
"Assumes char is 8 bits");
+ assert(PP.getTargetInfo().getIntWidth() <= 64 &&
+ (PP.getTargetInfo().getIntWidth() & 7) == 0 &&
+ "Assumes sizeof(int) on target is <= 64 and a multiple of char");
+ assert(PP.getTargetInfo().getWCharWidth() <= 64 &&
+ "Assumes sizeof(wchar) on target is <= 64");
// This is what we will use for overflow detection
llvm::APInt LitVal(PP.getTargetInfo().getIntWidth(), 0);
- bool isFirstChar = true;
- bool isMultiChar = false;
+ unsigned NumCharsSoFar = 0;
while (begin[0] != '\'') {
uint64_t ResultChar;
if (begin[0] != '\\') // If this is a normal character, consume it.
@@ -653,33 +653,33 @@
// If this is a multi-character constant (e.g. 'abc'), handle it. These are
// implementation defined (C99 6.4.4.4p10).
- if (!isFirstChar) {
- // If this is the second character being processed, do special handling.
- if (!isMultiChar) {
- isMultiChar = true;
-
- // Warn about discarding the top bits for multi-char wide-character
- // constants (L'abcd').
- if (IsWide)
- PP.Diag(Loc, diag::warn_extraneous_wide_char_constant);
- else
- PP.Diag(Loc, diag::ext_multichar_character_literal);
- }
-
+ if (NumCharsSoFar) {
if (IsWide) {
// Emulate GCC's (unintentional?) behavior: L'ab' -> L'b'.
LitVal = 0;
} else {
// Narrow character literals act as though their value is concatenated
- // in this implementation.
- if ((LitVal.shl(8)).lshr(8) != LitVal)
+ // in this implementation, but warn on overflow.
+ if (LitVal.countLeadingZeros() < 8)
PP.Diag(Loc, diag::warn_char_constant_too_large);
LitVal <<= 8;
}
}
LitVal = LitVal + ResultChar;
- isFirstChar = false;
+ ++NumCharsSoFar;
+ }
+
+ // If this is the second character being processed, do special handling.
+ if (NumCharsSoFar > 1) {
+ // Warn about discarding the top bits for multi-char wide-character
+ // constants (L'abcd').
+ if (IsWide)
+ PP.Diag(Loc, diag::warn_extraneous_wide_char_constant);
+ else if (NumCharsSoFar != 4)
+ PP.Diag(Loc, diag::ext_multichar_character_literal);
+ else
+ PP.Diag(Loc, diag::ext_four_char_character_literal);
}
// Transfer the value from APInt to uint64_t
@@ -689,7 +689,7 @@
// if 'char' is signed for this target (C99 6.4.4.4p10). Note that multiple
// character constants are not sign extended in the this implementation:
// '\xFF\xFF' = 65536 and '\x0\xFF' = 255, which matches GCC.
- if (!IsWide && !isMultiChar && (Value & 128) &&
+ if (!IsWide && NumCharsSoFar == 1 && (Value & 128) &&
PP.getTargetInfo().isCharSigned())
Value = (signed char)Value;
}
Modified: cfe/trunk/test/Lexer/constants.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Lexer/constants.c?rev=70329&r1=70328&r2=70329&view=diff
==============================================================================
--- cfe/trunk/test/Lexer/constants.c (original)
+++ cfe/trunk/test/Lexer/constants.c Tue Apr 28 16:51:46 2009
@@ -16,14 +16,20 @@
char c[] = {
- 'df', // expected-warning {{multi-character character constant}}
+ 'df', // expected-warning {{multi-character character constant}}
'\t',
'\\
t',
- '??!' // expected-warning {{trigraph converted to '|' character}}
+ '??!', // expected-warning {{trigraph converted to '|' character}}
+ 'abcd' // expected-warning {{multi-character character constant}}
};
#pragma GCC diagnostic ignored "-Wmultichar"
char d = 'df'; // no warning.
+char e = 'abcd'; // still warn: expected-warning {{multi-character character constant}}
+
+#pragma GCC diagnostic ignored "-Wfour-char-constants"
+
+char f = 'abcd'; // ignored.
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