case situations with the unary operators & and *. Also extend the array bounds
checking to work with pointer arithmetic; the pointer arithemtic checking can
be turned on using -Warray-bounds-pointer-arithmetic.
The changes to where CheckArrayAccess gets called is based on some trial &
error and a bunch of digging through source code and gdb backtraces in order
to have the check performed under as many situations as possible (such as for
variable initializers, arguments to function calls, and within conditional in
addition to the simpler cases of the operands to binary and unary operator)
while not being called--and triggering warnings--more than once for a given
ArraySubscriptExpr.
llvm-svn: 136997
arrays. This now suppresses the warning only in the case of
a one-element array as the last field in a struct where the array size
is a literal '1' rather than any macro expansion or template parameter.
This doesn't distinguish between the language standard in use to allow
code which dates from C89 era to compile without the warning even in C99
and C++ builds. We could add a separate warning (under a different flag)
with fixit hints to switch to a flexible array, but its not clear that
this would be desirable. Much of the code using this idiom is striving
for maximum portability.
Tests were also fleshed out a bit, and the diagnostic itself tweaked to
be more pretty w.r.t. single elment arrays. This is more ugly than
I would like due to APInt's not being supported by the diagnostic
rendering engine.
A pseudo-patch for this was proposed by Nicola Gigante, but I reworked
it both for several correctness issues and for code style.
Sorry this was so long in coming.
llvm-svn: 136965
has a single element. This disables the warning in cases where
there is a clear bug, but this is really rare (who uses arrays
with one element?) and it also silences a large class of false
positive issues with C89 code that is using tail padding in structs.
A better version of this patch would detect when an array is in
a tail position in a struct, but at least patch fixes the huge
false positives that are hitting postgres and other code.
llvm-svn: 136724
and to work with pointer arithmetic in addition to array indexing.
The new pointer arithmetic porition of the array bounds checking can be
turned on by -Warray-bounds-pointer-arithmetic (and is off by default).
llvm-svn: 136046
diagnostics that occur in unreachable code (e.g., -Warray-bound).
We only pay the cost of doing the reachability analysis when we issue one of these diagnostics.
llvm-svn: 126290
especially C++ code, and generally expand the test coverage.
Logic adapted from a patch by Kaelyn Uhrain <rikka@google.com> and
another Googler.
llvm-svn: 125775
Matt Beaumont-Gay