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Uninitialized pointers: It's allowed to dereference uninitialized non-pointer variables

This commit is contained in:
Daniel Marjamäki 2009-10-30 14:31:37 +01:00
parent 44a9c9b458
commit 765c824c6f
2 changed files with 30 additions and 6 deletions
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21
lib/checkother.cpp
View File

@ -1160,7 +1160,7 @@ void CheckOther::nullPointer()
nullPointerConditionalAssignment(); nullPointerConditionalAssignment();
} }
static const Token *uninitvar_checkscope(const Token *tok, const unsigned int varid, bool &init) static const Token *uninitvar_checkscope(const Token *tok, const unsigned int varid, bool &init, const bool pointer)
{ {
/* limit the checking in conditional code.. /* limit the checking in conditional code..
* int x; * int x;
@ -1203,7 +1203,7 @@ static const Token *uninitvar_checkscope(const Token *tok, const unsigned int va
// Recursively check into the if .. // Recursively check into the if ..
bool init2 = false; bool init2 = false;
const Token *tokerr = uninitvar_checkscope(tok->next(), varid, init2); const Token *tokerr = uninitvar_checkscope(tok->next(), varid, init2, pointer);
if (!limit && tokerr) if (!limit && tokerr)
return tokerr; return tokerr;
@ -1228,7 +1228,7 @@ static const Token *uninitvar_checkscope(const Token *tok, const unsigned int va
// there is no "if".. // there is no "if"..
init2 = false; init2 = false;
tokerr = uninitvar_checkscope(tok->next(), varid, init2); tokerr = uninitvar_checkscope(tok->next(), varid, init2, pointer);
if (!limit && tokerr) if (!limit && tokerr)
return tokerr; return tokerr;
@ -1283,8 +1283,14 @@ static const Token *uninitvar_checkscope(const Token *tok, const unsigned int va
} }
} }
if (Token::Match(tok, "return| %varid% .|", varid)) if (tok->varId() == varid)
return tok; {
if (Token::simpleMatch(tok->previous(), "return"))
return tok;
if (pointer && Token::simpleMatch(tok->next(), "."))
return tok;
}
} }
return 0; return 0;
} }
@ -1309,6 +1315,9 @@ void CheckOther::uninitvar()
} }
if (Token::Match(tok, "[{};] %type% *| %var% ;")) if (Token::Match(tok, "[{};] %type% *| %var% ;"))
{ {
// if it's a pointer, dereferencing is forbidden
const bool pointer(tok->strAt(2) == std::string("*"));
// goto the variable // goto the variable
tok = tok->tokAt(2); tok = tok->tokAt(2);
if (tok->str() == "*") if (tok->str() == "*")
@ -1320,7 +1329,7 @@ void CheckOther::uninitvar()
// check if variable is accessed uninitialized.. // check if variable is accessed uninitialized..
bool init = false; bool init = false;
const Token *tokerr = uninitvar_checkscope(tok->next(), tok->varId(), init); const Token *tokerr = uninitvar_checkscope(tok->next(), tok->varId(), init, pointer);
if (tokerr) if (tokerr)
uninitvarError(tokerr, tok->str()); uninitvarError(tokerr, tok->str());
} }

15
test/testother.cpp
View File

@ -933,6 +933,21 @@ private:
void uninitvar1() void uninitvar1()
{ {
// dereferencing uninitialized pointer..
checkUninitVar("static void foo()\n"
"{\n"
" Foo *p;\n"
" p->abcd();\n"
"}\n");
ASSERT_EQUALS("[test.cpp:4]: (error) Uninitialized variable: p\n", errout.str());
checkUninitVar("static void foo()\n"
"{\n"
" Foo p;\n"
" p.abcd();\n"
"}\n");
ASSERT_EQUALS("", errout.str());
// if.. // if..
checkUninitVar("static void foo()\n" checkUninitVar("static void foo()\n"
"{\n" "{\n"