Commit Graph

20 Commits

Author SHA1 Message Date
Anders Carlsson
801c5c7467 GCC has an extension where the left hand side of the ? : operator can be omitted. Handle this in a few more places.
llvm-svn: 44462
2007-11-30 19:04:31 +00:00
Ted Kremenek
eda40e273e Enhanced implementation of -Wfloat-equal to check for comparisons against
floating-point literals that are represented exactly by the APFloat in
FloatingLiteral. For such literals, we do not emit a warning since such checks are
often performed in real code to see if a variable has changed from its original
value. This heuristic clearly can lead to false negatives, but the hope is it will
significantly reduce false positives to help make the compiler flag more useful.

llvm-svn: 44424
2007-11-29 00:59:04 +00:00
Ted Kremenek
43fb8b0799 Moved logic for -Wfloat-equal to SemaChecking.cpp.
Moved utility functions IgnoreParen and friends to be static inline functions
defined in SemaUtil.h.

Added SemaUtil.h to Xcode project.

llvm-svn: 44312
2007-11-25 00:58:00 +00:00
Ted Kremenek
41362cea7b Added notion of '*' specified format width/specifiers when checking
printf format strings.  Added type checking to see if the matching
width/precision argument was of type 'int'.

Thanks to Anders Carlsson for reporting this missing feature.

llvm-svn: 42933
2007-10-12 20:51:52 +00:00
Anders Carlsson
431ef632cb Add some more diagnostics for va_start, fix tests so they pass with these new diags.
llvm-svn: 42917
2007-10-12 17:48:41 +00:00
Ted Kremenek
6a6c08c319 Printf argument checking now supports dynamically-passed precision
specifiers.

llvm-svn: 42886
2007-10-12 00:11:27 +00:00
Chris Lattner
55343038f4 Fix 80 col violations.
llvm-svn: 41611
2007-08-30 17:08:17 +00:00
Ted Kremenek
e07a8cd7ff Fixed return-of-stack-address checker to correctly handle stack/global
variables that have a pointer type, or arrays that contain pointers.

This fixes a crash on the following code:

int *h[3];

int **foo(int i)
{
   return &(h[i]);
}

This bug was reported by Keith Bauer (thanks!).

llvm-svn: 41546
2007-08-28 17:02:55 +00:00
Ted Kremenek
d11e460810 Updated checker for "return of address of stack variable" to look for
implicit casts from T to T& at the topmost part of the return-value expression.

This checking may be needed within EvalAddr later on.  We'll wait until
test cases show this kind of logic is necessary (as more C++ features are
implemented in clang).

llvm-svn: 41493
2007-08-27 16:39:17 +00:00
Chris Lattner
0c6aad373f Fix %p format checking, patch by Keith Bauer.
llvm-svn: 41454
2007-08-26 17:39:38 +00:00
Chris Lattner
0d850bfed8 For warnings like this:
t.c:3:9: warning: invalid conversion '%B'
printf("%B\a\n", p);
~~~~~~  ^

Don't beep the console or print the newline.

llvm-svn: 41453
2007-08-26 17:38:22 +00:00
Chris Lattner
e33fbdb898 Fix the test/Sema/format-strings.c regression. This code should be refactored.
llvm-svn: 41398
2007-08-25 05:36:18 +00:00
Chris Lattner
9449fd7bc3 Fix the regression on test/Sema/cfstring.c
llvm-svn: 41396
2007-08-25 05:30:33 +00:00
Ted Kremenek
c81614d5d1 Modified ArraySubscriptExpr to have accessors getLHS and getRHS in addition
to getBase and getIdx.  getBase and getIdx now return a "normalized" view
of the expression (e.g., always "A[4]" instead of possibly "4[A]").  getLHS
and getRHS return the expressions with syntactic fidelity to the original
source code.

Also modified client code of ArraySubscriptExpr, including the AST dumper
and pretty printer, the return-stack value checker, and the LLVM code
generator.

llvm-svn: 41180
2007-08-20 16:18:38 +00:00
Ted Kremenek
cff94fa201 Added extra semantic checking to do basic detection of
"return of stack addresses."  ParseReturnStmt now calls CheckReturnStackAddr
to determine if the expression in the return statement evaluates to an
address of a stack variable.  If so, we issue a warning. 

llvm-svn: 41141
2007-08-17 16:46:58 +00:00
Anders Carlsson
a3a9c43837 Return true in case of error, which is what other functions do.
llvm-svn: 41140
2007-08-17 15:44:17 +00:00
Anders Carlsson
98f0790fab Add initial support for constant CFStrings.
llvm-svn: 41136
2007-08-17 05:31:46 +00:00
Ted Kremenek
e68f1aad65 Added support for additional format string checking for the printf
family of functions.  Previous functionality only included checking to
see if the format string was a string literal.  Now we check parse the
format string (if it is a literal) and perform the following checks:

(1) Warn if: number conversions (e.g. "%d") != number data arguments.

(2) Warn about missing format strings  (e.g., "printf()").

(3) Warn if the format string is not a string literal.

(4) Warn about the use se of '%n' conversion.  This conversion is
    discouraged for security reasons.

(5) Warn about malformed conversions.  For example '%;', '%v'; these
    are not valid.

(6) Warn about empty format strings; e.g. printf("").  Although these
    can be optimized away by the compiler, they can be indicative of
    broken programmer logic.  We may need to add additional support to
    see when such cases occur within macro expansion to avoid false
    positives.

(7) Warn if the string literal is wide; e.g. L"%d".

(8) Warn if we detect a '\0' character WITHIN the format string.

Test cases are included.

llvm-svn: 41076
2007-08-14 17:39:48 +00:00
Ted Kremenek
56c864e3fd Added "id_idx" parameter to CheckPrintfArguments. This will be used
by CheckPrintfArguments to determine if a given printf function
accepts a va_arg argument.

llvm-svn: 41008
2007-08-10 21:21:05 +00:00
Chris Lattner
b87b1b36ee initial support for checking format strings, patch by Ted Kremenek:
"I've coded up some support in clang to flag warnings for non-constant format strings used in calls to printf-like functions (all the functions listed in "man fprintf").  Non-constant format strings are a source of many security exploits in C/C++ programs, and I believe are currently detected by gcc using the flag -Wformat-nonliteral."

llvm-svn: 41003
2007-08-10 20:18:51 +00:00