incorrectly in the CFG, and also the static analyzer. This patch regresses the analyzer a bit, but
that needs to be followed up with a better solution.
Fixes <rdar://problem/10008112>.
llvm-svn: 138372
AnalysisBasedWarnings Sema layer and out of the Analysis library itself.
This returns the uninitialized values analysis to a more pure form,
allowing its original logic to correctly detect some categories of
definitely uninitialized values. Fixes PR10358 (again).
Thanks to Ted for reviewing and updating this patch after his rewrite of
several portions of this analysis.
llvm-svn: 135748
patch, we actually move the state-machine for the value set backwards
one step. This can pretty easily lead to infinite loops where we
continually try to propagate a bit, succeed for one iteration, but then
back up because we find an uninitialized use.
A reduced test case from PR10379 is included.
llvm-svn: 135359
definitely have a path leading to them, and possibly have a path leading
to them; reflect that distinction in the warning text emitted.
llvm-svn: 129126
marked explicitly as uninitialized through direct self initialization:
int x = x;
With r128894 we prevented warnings about this code, and this patch
teaches the analysis engine to continue analyzing subsequent uses of
'x'. This should wrap up PR9624.
There is still an open question of whether we should suppress the
maybe-uninitialized warnings resulting from variables initialized in
this fashion. The definitely-uninitialized uses should always be warned.
llvm-svn: 128932
int x = x;
GCC disables its warnings on this construct as a way of indicating that
the programmer intentionally wants the variable to be uninitialized.
Only the warning on the initializer is turned off in this iteration.
This makes the code a lot more ugly, but starts commenting the
surprising behavior here. This is a WIP, I want to refactor it
substantially for clarity, and to determine whether subsequent warnings
should be suppressed or not.
llvm-svn: 128894
1) Change the CFG to include the DeclStmt for conditional variables, instead of using the condition itself as a faux DeclStmt.
2) Update ExprEngine (the static analyzer) to understand (1), so not to regress.
3) Update UninitializedValues.cpp to initialize all tracked variables to Uninitialized at the start of the function/method.
4) Only use the SelfReferenceChecker (SemaDecl.cpp) on global variables, leaving the dataflow analysis to handle other cases.
The combination of (1) and (3) allows the dataflow-based -Wuninitialized to find self-init problems when the initializer
contained control-flow.
llvm-svn: 128858
Note this can potentially be enhanced to detect if the __block variable
is actually written by the block, or only when the block "escapes" or
is actually used, but that requires more analysis than it is probably worth
for this simple check.
llvm-svn: 128681
to issue the warning at an uninitialized variable's
declaration, but to issue notes at possible
uninitialized uses (which could be multiple).
llvm-svn: 123994
analysis for short-circuited operations. For branch written like "if (x && y)",
we maintain two sets of dataflow values for the outgoing
branches. This suppresses some common false positives
for -Wuninitialized-experimental.
This change introduces some assertion failures
when running on the LLVM codebase. WIP.
llvm-svn: 123923
references by monitoring whether an access to
a variable is solely to compute it's lvalue or
to do an lvalue-to-rvalue conversion (i.e., a load).
llvm-svn: 123777
Matt Beaumont-Gay