diff options
Diffstat (limited to 'test/Analysis/comparison-implicit-casts.cpp')
-rw-r--r-- | test/Analysis/comparison-implicit-casts.cpp | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/test/Analysis/comparison-implicit-casts.cpp b/test/Analysis/comparison-implicit-casts.cpp new file mode 100644 index 0000000..df9d870 --- /dev/null +++ b/test/Analysis/comparison-implicit-casts.cpp @@ -0,0 +1,98 @@ +// RUN: %clang_cc1 -analyze -analyzer-checker=core,unix.cstring,debug.ExprInspection -analyzer-constraints=basic -triple i386-apple-darwin9 -verify %s +// RUN: %clang_cc1 -analyze -analyzer-checker=core,unix.cstring,debug.ExprInspection -analyzer-constraints=basic -triple x86_64-apple-darwin9 -verify %s +// RUN: %clang_cc1 -analyze -analyzer-checker=core,unix.cstring,debug.ExprInspection -analyzer-constraints=range -triple i386-apple-darwin9 -verify %s +// RUN: %clang_cc1 -analyze -analyzer-checker=core,unix.cstring,debug.ExprInspection -analyzer-constraints=range -triple x86_64-apple-darwin9 -verify %s + +// This file runs in C++ mode so that the comparison type is 'bool', not 'int'. +void clang_analyzer_eval(int); +typedef typeof(sizeof(int)) size_t; + +// PR12206/12510 - When SimpleSValBuilder figures out that a symbol is fully +// constrained, it should cast the value to the result type in a binary +// operation...unless the binary operation is a comparison, in which case the +// two arguments should be the same type, but won't match the result type. +// +// This is not directly related to additive folding, but we use SValBuilder's +// additive folding to tickle the bug. ExprEngine will simplify fully-constrained +// symbols, so SValBuilder will only see them if they are (a) part of an evaluated +// SymExpr (e.g. with additive folding) or (b) generated by a checker (e.g. +// unix.cstring's strlen() modelling). +void PR12206(int x) { + size_t comparisonSize = sizeof(1 == 1); + + // Sanity check. This test is useless if size_t isn't bigger than bool. + clang_analyzer_eval(sizeof(size_t) > comparisonSize); // expected-warning{{TRUE}} + + // Build a SymIntExpr, dependent on x. + int local = x - 1; + + // Create a value that requires more bits to store than a comparison result. + int value = 1; + value <<= 8 * comparisonSize; + value += 1; + + // Constrain the value of x. + if (x != value) return; + + // Constant-folding will turn (local+1) back into the symbol for x. + // The point of this dance is to make SValBuilder be responsible for + // turning the symbol into a ConcreteInt, rather than ExprEngine. + + // Test relational operators. + clang_analyzer_eval((local + 1) >= 2); // expected-warning{{TRUE}} + clang_analyzer_eval(2 <= (local + 1)); // expected-warning{{TRUE}} + + // Test equality operators. + clang_analyzer_eval((local + 1) != 1); // expected-warning{{TRUE}} + clang_analyzer_eval(1 != (local + 1)); // expected-warning{{TRUE}} +} + +void PR12206_truncation(signed char x) { + // Build a SymIntExpr, dependent on x. + signed char local = x - 1; + + // Constrain the value of x. + if (x != 1) return; + + // Constant-folding will turn (local+1) back into the symbol for x. + // The point of this dance is to make SValBuilder be responsible for + // turning the symbol into a ConcreteInt, rather than ExprEngine. + + // Construct a value that cannot be represented by 'char', + // but that has the same lower bits as x. + signed int value = 1 + (1 << 8); + + // Test relational operators. + clang_analyzer_eval((local + 1) < value); // expected-warning{{TRUE}} + clang_analyzer_eval(value > (local + 1)); // expected-warning{{TRUE}} + + // Test equality operators. + clang_analyzer_eval((local + 1) != value); // expected-warning{{TRUE}} + clang_analyzer_eval(value != (local + 1)); // expected-warning{{TRUE}} +} + +// This test is insurance in case we significantly change how SymExprs are +// evaluated. +size_t strlen(const char *s); +void PR12206_strlen(const char *x) { + size_t comparisonSize = sizeof(1 == 1); + + // Sanity check. This test is useless if size_t isn't bigger than bool. + clang_analyzer_eval(sizeof(size_t) > comparisonSize); // expected-warning{{TRUE}} + + // Create a value that requires more bits to store than a comparison result. + size_t value = 1UL; + value <<= 8 * comparisonSize; + value += 1; + + // Constrain the length of x. + if (strlen(x) != value) return; + + // Test relational operators. + clang_analyzer_eval(strlen(x) >= 2); // expected-warning{{TRUE}} + clang_analyzer_eval(2 <= strlen(x)); // expected-warning{{TRUE}} + + // Test equality operators. + clang_analyzer_eval(strlen(x) != 1); // expected-warning{{TRUE}} + clang_analyzer_eval(1 != strlen(x)); // expected-warning{{TRUE}} +} |