diff options
| author | Ted Kremenek <kremenek@apple.com> | 2010-10-18 23:36:05 +0000 |
|---|---|---|
| committer | Ted Kremenek <kremenek@apple.com> | 2010-10-18 23:36:05 +0000 |
| commit | 6648e5d387b5402eae6a597bd46709ac445b4156 (patch) | |
| tree | 4a158d218e738322a972d1893ed5609a22404174 | |
| parent | 25b26ebdebe46bb4576247e0c64d1c11410a8e9d (diff) | |
"Fix" bogus idempotent operations warning due to loop unrolling not unrolling enough loops to show that an invariant
doesn't hold. This fix is to increase the loop unrolling count to 4, which experiments show doesn't typically impact
analysis time. The real fix is to modify the IdempotentOperationsChecker to suppress warnings where an analysis point
could be preceded by a point where we gave up due to loop unrolling.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@116769 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/Frontend/CompilerInvocation.cpp | 2 | ||||
| -rw-r--r-- | test/Analysis/idempotent-operations-limited-loops.c | 29 |
2 files changed, 30 insertions, 1 deletions
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp index fd9b635997..70bdd5b99c 100644 --- a/lib/Frontend/CompilerInvocation.cpp +++ b/lib/Frontend/CompilerInvocation.cpp @@ -830,7 +830,7 @@ static void ParseAnalyzerArgs(AnalyzerOptions &Opts, ArgList &Args, Args.hasArg(OPT_analyzer_experimental_internal_checks); Opts.TrimGraph = Args.hasArg(OPT_trim_egraph); Opts.MaxNodes = Args.getLastArgIntValue(OPT_analyzer_max_nodes, 150000,Diags); - Opts.MaxLoop = Args.getLastArgIntValue(OPT_analyzer_max_loop, 3, Diags); + Opts.MaxLoop = Args.getLastArgIntValue(OPT_analyzer_max_loop, 4, Diags); Opts.InlineCall = Args.hasArg(OPT_analyzer_inline_call); Opts.IdempotentOps = Args.hasArg(OPT_analysis_WarnIdempotentOps); } diff --git a/test/Analysis/idempotent-operations-limited-loops.c b/test/Analysis/idempotent-operations-limited-loops.c new file mode 100644 index 0000000000..e3043ee014 --- /dev/null +++ b/test/Analysis/idempotent-operations-limited-loops.c @@ -0,0 +1,29 @@ +void always_warning() { int *p = 0; *p = 0xDEADBEEF; } + +// FIXME: False positive due to loop unrolling. This should be fixed. + +int pr8403() +{ + int i; + for(i=0; i<10; i++) + { + int j; + for(j=0; j+1<i; j++) + { + } + } + return 0; +} + +// RUN: %clang_cc1 -analyze -analyzer-store=region -analyzer-constraints=range -fblocks -analyzer-opt-analyze-nested-blocks -analyzer-check-objc-mem -analyzer-check-idempotent-operations -analyzer-max-loop 3 %s 2>&1 | FileCheck --check-prefix=Loops3 %s +// RUN: %clang_cc1 -analyze -analyzer-store=region -analyzer-constraints=range -fblocks -analyzer-opt-analyze-nested-blocks -analyzer-check-objc-mem -analyzer-check-idempotent-operations -analyzer-max-loop 4 %s 2>&1 | FileCheck --check-prefix=Loops4 %s +// RUN: %clang_cc1 -analyze -analyzer-store=region -analyzer-constraints=range -fblocks -analyzer-opt-analyze-nested-blocks -analyzer-check-objc-mem -analyzer-check-idempotent-operations %s 2>&1 | FileCheck --check-prefix=LoopsDefault %s + +// CHECK-Loops3: :1:37: warning: Dereference of null pointer +// CHECK-Loops3: :11:27: warning: The left operand to '+' is always 0 +// CHECK-Loops3: 2 warnings generated +// CHECK-Loops4: :1:37: warning: Dereference of null pointer +// CHECK-Loops4: 1 warning generated. +// CHECK-LoopsDefault: :1:37: warning: Dereference of null pointer +// CHECK-LoopsDefault: 1 warning generated. + |