f68c0a2f58
The patch is straightforward except the tiny fix in BugReporterVisitors.cpp that suppresses a default note for "Assuming pointer value is null" when a note tag from the checker is present. This is probably the right thing to do but also definitely not a complete solution to the problem of different sources of path notes being unaware of each other, which is a large and annoying issue that we have to deal with. Note tags really help there because they're nicely introspectable. The problem is demonstrated by the newly added getenv() test. Differential Revision: https://reviews.llvm.org/D122285
61 lines
1.9 KiB
C
61 lines
1.9 KiB
C
// RUN: %clang_analyze_cc1 -verify %s \
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// RUN: -analyzer-checker=core,apiModeling \
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// RUN: -analyzer-output=text
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#define NULL ((void *)0)
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char *getenv(const char *);
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int isalpha(int);
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int isdigit(int);
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int islower(int);
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char test_getenv() {
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char *env = getenv("VAR"); // \
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// expected-note{{Assuming the environment variable does not exist}} \
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// expected-note{{'env' initialized here}}
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return env[0]; // \
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// expected-warning{{Array access (from variable 'env') results in a null pointer dereference}} \
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// expected-note {{Array access (from variable 'env') results in a null pointer dereference}}
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}
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int test_isalpha(int *x, char c) {
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if (isalpha(c)) {// \
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// expected-note{{Assuming the character is alphabetical}} \
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// expected-note{{Taking true branch}}
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x = NULL; // \
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// expected-note{{Null pointer value stored to 'x'}}
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}
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return *x; // \
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// expected-warning{{Dereference of null pointer (loaded from variable 'x')}} \
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// expected-note {{Dereference of null pointer (loaded from variable 'x')}}
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}
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int test_isdigit(int *x, char c) {
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if (!isdigit(c)) {// \
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// expected-note{{Assuming the character is not a digit}} \
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// expected-note{{Taking true branch}}
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x = NULL; // \
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// expected-note{{Null pointer value stored to 'x'}}
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}
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return *x; // \
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// expected-warning{{Dereference of null pointer (loaded from variable 'x')}} \
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// expected-note {{Dereference of null pointer (loaded from variable 'x')}}
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}
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int test_islower(int *x) {
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char c = 'c';
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// No "Assuming..." note. We aren't assuming anything. We *know*.
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if (islower(c)) { // \
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// expected-note{{Taking true branch}}
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x = NULL; // \
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// expected-note{{Null pointer value stored to 'x'}}
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}
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return *x; // \
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// expected-warning{{Dereference of null pointer (loaded from variable 'x')}} \
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// expected-note {{Dereference of null pointer (loaded from variable 'x')}}
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}
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