Patch by Cristian Draghici:
Enhance the printf format string checking when using the format
specifier flags ' ', '0', '+' with the 'p' or 's' conversions (since
they are nonsensical and undefined). This is similar to GCC's
checking.
Also warning when a precision is used with the 'p' conversin
specifier, since it has no meaning.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@95869 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 8451023..3a77552 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -1080,6 +1080,9 @@
bool HandleAmount(const analyze_printf::OptionalAmount &Amt,
unsigned MissingArgDiag, unsigned BadTypeDiag,
const char *startSpecifier, unsigned specifierLen);
+ void HandleFlags(const analyze_printf::FormatSpecifier &FS,
+ llvm::StringRef flag, llvm::StringRef cspec,
+ const char *startSpecifier, unsigned specifierLen);
bool MatchType(QualType A, QualType B, bool ignoreSign);
@@ -1175,6 +1178,16 @@
return false;
}
+void CheckPrintfHandler::HandleFlags(const analyze_printf::FormatSpecifier &FS,
+ llvm::StringRef flag,
+ llvm::StringRef cspec,
+ const char *startSpecifier,
+ unsigned specifierLen) {
+ const analyze_printf::ConversionSpecifier &CS = FS.getConversionSpecifier();
+ S.Diag(getLocationOfByte(CS.getStart()), diag::warn_printf_nonsensical_flag)
+ << flag << cspec << getFormatSpecifierRange(startSpecifier, specifierLen);
+}
+
bool
CheckPrintfHandler::HandleAmount(const analyze_printf::OptionalAmount &Amt,
unsigned MissingArgDiag,
@@ -1214,7 +1227,8 @@
}
bool
-CheckPrintfHandler::HandleFormatSpecifier(const analyze_printf::FormatSpecifier &FS,
+CheckPrintfHandler::HandleFormatSpecifier(const analyze_printf::FormatSpecifier
+ &FS,
const char *startSpecifier,
unsigned specifierLen) {
@@ -1262,7 +1276,25 @@
// Continue checking the other format specifiers.
return true;
}
-
+
+ if (CS.getKind() == ConversionSpecifier::VoidPtrArg) {
+ if (FS.getPrecision().getHowSpecified() != OptionalAmount::NotSpecified)
+ S.Diag(getLocationOfByte(CS.getStart()),
+ diag::warn_printf_nonsensical_precision)
+ << CS.getCharacters()
+ << getFormatSpecifierRange(startSpecifier, specifierLen);
+ }
+ if (CS.getKind() == ConversionSpecifier::VoidPtrArg ||
+ CS.getKind() == ConversionSpecifier::CStrArg) {
+ // FIXME: Instead of using "0", "+", etc., eventually get them from
+ // the FormatSpecifier.
+ if (FS.hasLeadingZeros())
+ HandleFlags(FS, "0", CS.getCharacters(), startSpecifier, specifierLen);
+ if (FS.hasPlusPrefix())
+ HandleFlags(FS, "+", CS.getCharacters(), startSpecifier, specifierLen);
+ if (FS.hasSpacePrefix())
+ HandleFlags(FS, " ", CS.getCharacters(), startSpecifier, specifierLen);
+ }
// The remaining checks depend on the data arguments.
if (HasVAListArg)