Fix #14457 (ValueType: char expression without signedness) (cppcheck-opensource#8174)

Author: danmar

lib/symboldatabase.cpp

@@ -1915,7 +1915,10 @@ void SymbolDatabase::setArrayDimensionsUsingValueFlow()
                 }
 
                 if (bits > 0 && bits <= 62) {
-                    if (dimension.tok->valueType()->sign == ValueType::Sign::UNSIGNED)
+                    auto sign = dimension.tok->valueType()->sign;
+                    if (sign == ValueType::Sign::UNKNOWN_SIGN && dimension.tok->valueType()->type == ValueType::Type::CHAR)
+                        sign = mDefaultSignedness;
+                    if (sign == ValueType::Sign::UNSIGNED)
                         dimension.num = 1LL << bits;
                     else
                         dimension.num = 1LL << (bits - 1);
@@ -7635,9 +7638,7 @@ static const Token* parsedecl(const Token* type,
 
     // Set signedness for integral types..
     if (valuetype->isIntegral() && valuetype->sign == ValueType::Sign::UNKNOWN_SIGN) {
-        if (valuetype->type == ValueType::Type::CHAR)
-            valuetype->sign = defaultSignedness;
-        else if (valuetype->type >= ValueType::Type::SHORT)
+        if (valuetype->type >= ValueType::Type::SHORT)
             valuetype->sign = ValueType::Sign::SIGNED;
     }
 
@@ -8755,7 +8756,7 @@ ValueType::MatchResult ValueType::matchParameter(const ValueType *call, const Va
             return ValueType::MatchResult::UNKNOWN;
     }
 
-    if (call->isIntegral() && func->isIntegral() && call->sign != ValueType::Sign::UNKNOWN_SIGN && func->sign != ValueType::Sign::UNKNOWN_SIGN && call->sign != func->sign)
+    if (call->isIntegral() && func->isIntegral() && call->sign != func->sign)
         return ValueType::MatchResult::FALLBACK1;
 
     if (func->reference != Reference::None && (func->constness > call->constness || func->volatileness > call->volatileness))

test/testclangimport.cpp

@@ -1328,7 +1328,7 @@ class TestClangImport : public TestFixture {
         const Token *tok = Token::findsimplematch(tokenizer.tokens(), "\"hello\"");
         ASSERT(!!tok);
         ASSERT(!!tok->valueType());
-        ASSERT_EQUALS("const signed char *", tok->valueType()->str());
+        ASSERT_EQUALS("const char *", tok->valueType()->str());
     }
 
     void stdinLoc() {

test/testcondition.cpp

@@ -4601,11 +4601,7 @@ class TestCondition : public TestFixture {
               "        if (o[1] == '\\0') {}\n"
               "    }\n"
               "}\n");
-        if (std::numeric_limits<char>::is_signed) {
-            ASSERT_EQUALS("[test.cpp:6:18]: (style) Condition 'o[1]=='\\0'' is always false [knownConditionTrueFalse]\n", errout_str());
-        } else {
-            ASSERT_EQUALS("[test.cpp:4:25] -> [test.cpp:6:18]: (style) Condition 'o[1]=='\\0'' is always false [knownConditionTrueFalse]\n", errout_str());
-        }
+        ASSERT_EQUALS("[test.cpp:6:18]: (style) Condition 'o[1]=='\\0'' is always false [knownConditionTrueFalse]\n", errout_str());
 
         check("void f(int x) {\n" // #11449
               "    int i = x;\n"
@@ -5354,11 +5350,7 @@ class TestCondition : public TestFixture {
               "       buffer.back() == '\\n' ||\n"
               "       buffer.back() == '\\0') {}\n"
               "}\n");
-        if (std::numeric_limits<char>::is_signed) {
-            ASSERT_EQUALS("[test.cpp:5:22]: (style) Condition 'buffer.back()=='\\0'' is always false [knownConditionTrueFalse]\n", errout_str());
-        } else {
-            ASSERT_EQUALS("[test.cpp:3:22] -> [test.cpp:5:22]: (style) Condition 'buffer.back()=='\\0'' is always false [knownConditionTrueFalse]\n", errout_str());
-        }
+        ASSERT_EQUALS("[test.cpp:5:22]: (style) Condition 'buffer.back()=='\\0'' is always false [knownConditionTrueFalse]\n", errout_str());
 
         // #9353
         check("struct X { std::string s; };\n"

test/testother.cpp

@@ -2341,7 +2341,7 @@ class TestOther : public TestFixture {
         checkInvalidPointerCast("void test(float* data) {\n"
                                 "    f.write((char*)data,sizeof(float));\n"
                                 "}", dinit(CheckInvalidPointerCastOptions, $.inconclusive = true)); // #3639
-        ASSERT_EQUALS("[test.cpp:2:13]: (portability, inconclusive) Casting from float * to signed char * is not portable due to different binary data representations on different platforms. [invalidPointerCast]\n", errout_str());
+        ASSERT_EQUALS("[test.cpp:2:13]: (portability, inconclusive) Casting from float * to char * is not portable due to different binary data representations on different platforms. [invalidPointerCast]\n", errout_str());
 
 
         checkInvalidPointerCast("long long* test(float* f) {\n"

test/testsymboldatabase.cpp

@@ -586,6 +586,7 @@ class TestSymbolDatabase : public TestFixture {
         TEST_CASE(valueType2);
         TEST_CASE(valueType3);
         TEST_CASE(valueTypeThis);
+        TEST_CASE(valueTypeChar);
 
         TEST_CASE(variadic1); // #7453
         TEST_CASE(variadic2); // #7649
@@ -7796,20 +7797,12 @@ class TestSymbolDatabase : public TestFixture {
         f = Token::findsimplematch(tokenizer.tokens(), "get ( get ( v7 ) ) ;");
         ASSERT(f);
         ASSERT(f->function());
-        if (std::numeric_limits<char>::is_signed) {
-            ASSERT_EQUALS(10, f->function()->tokenDef->linenr());
-        } else {
-            ASSERT_EQUALS(5, f->function()->tokenDef->linenr());
-        }
+        ASSERT_EQUALS(10, f->function()->tokenDef->linenr());
 
         f = Token::findsimplematch(tokenizer.tokens(), "get ( get ( v8 ) ) ;");
         ASSERT(f);
         ASSERT(f->function());
-        if (std::numeric_limits<char>::is_signed) {
-            ASSERT_EQUALS(5, f->function()->tokenDef->linenr());
-        } else {
-            ASSERT_EQUALS(11, f->function()->tokenDef->linenr());
-        }
+        ASSERT_EQUALS(11, f->function()->tokenDef->linenr());
 
         f = Token::findsimplematch(tokenizer.tokens(), "get ( get ( v9 ) ) ;");
         ASSERT(f);
@@ -10145,6 +10138,13 @@ class TestSymbolDatabase : public TestFixture {
         ASSERT_EQUALS("const C *", typeOf("class C { void foo() const; }; void C::foo() const { *this = 0; }", "this"));
     }
 
+    void valueTypeChar() {
+        Settings s = settings2;
+        s.platform.defaultSign = 's';
+        ASSERT_EQUALS("char", typeOf("char c; c = 'x';", "c =", true, &s));
+        ASSERT_EQUALS("char", typeOf("char buf[10]; buf[0] = 'x';", "[ 0 ]", true, &s));
+    }
+
     void variadic1() { // #7453
         {
             GET_SYMBOL_DB("CBase* create(const char *c1, ...);\n"