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cppcheck/test/testincompletestatement.cpp

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/*
* Cppcheck - A tool for static C/C++ code analysis
* Copyright (C) 2007-2023 Cppcheck team.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "checkother.h"
#include "errortypes.h"
#include "helpers.h"
#include "settings.h"
#include "fixture.h"
#include "tokenize.h"
#include <sstream> // IWYU pragma: keep
#include <string>
#include <vector>
class TestIncompleteStatement : public TestFixture {
public:
TestIncompleteStatement() : TestFixture("TestIncompleteStatement") {}
private:
const Settings settings = settingsBuilder().severity(Severity::warning).build();
#define check(...) check_(__FILE__, __LINE__, __VA_ARGS__)
void check_(const char* file, int line, const char code[], bool inconclusive = false) {
// Clear the error buffer..
errout.str("");
const Settings settings1 = settingsBuilder(settings).certainty(Certainty::inconclusive, inconclusive).build();
std::vector<std::string> files(1, "test.cpp");
Tokenizer tokenizer(&settings1, this);
PreprocessorHelper::preprocess(code, files, tokenizer);
// Tokenize..
ASSERT_LOC(tokenizer.simplifyTokens1(""), file, line);
// Check for incomplete statements..
CheckOther checkOther(&tokenizer, &settings1, this);
checkOther.checkIncompleteStatement();
}
void run() override {
TEST_CASE(test1);
TEST_CASE(test2);
TEST_CASE(test3);
TEST_CASE(test4);
TEST_CASE(test5);
TEST_CASE(test6);
TEST_CASE(test7);
TEST_CASE(test_numeric);
TEST_CASE(void0); // #6327: No fp for statement "(void)0;"
TEST_CASE(intarray);
TEST_CASE(structarraynull);
TEST_CASE(structarray);
TEST_CASE(conditionalcall); // ; 0==x ? X() : Y();
TEST_CASE(structinit); // #2462 : ABC abc{1,2,3};
TEST_CASE(returnstruct);
TEST_CASE(cast); // #3009 : (struct Foo *)123.a = 1;
TEST_CASE(increment); // #3251 : FP for increment
TEST_CASE(cpp11init); // #5493 : int i{1};
TEST_CASE(cpp11init2); // #8449
TEST_CASE(cpp11init3); // #8995
TEST_CASE(block); // ({ do_something(); 0; })
TEST_CASE(mapindex);
TEST_CASE(commaoperator1);
TEST_CASE(commaoperator2);
TEST_CASE(redundantstmts);
TEST_CASE(vardecl);
TEST_CASE(archive); // ar & x
TEST_CASE(ast);
TEST_CASE(oror); // dostuff() || x=32;
}
void test1() {
check("void foo()\n"
"{\n"
" const char def[] =\n"
" \"abc\";\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void test2() {
check("void foo()\n"
"{\n"
" \"abc\";\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (warning) Redundant code: Found a statement that begins with string constant.\n", errout.str());
}
void test3() {
check("void foo()\n"
"{\n"
" const char *str[] = { \"abc\" };\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void test4() {
check("void foo()\n"
"{\n"
"const char *a =\n"
"{\n"
"\"hello \"\n"
"\"more \"\n"
"\"world\"\n"
"};\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void test5() {
check("void foo()\n"
"{\n"
" 50;\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (warning) Redundant code: Found a statement that begins with numeric constant.\n", errout.str());
}
void test6() {
// don't crash
check("void f() {\n"
" 1 == (two + three);\n"
" 2 != (two + three);\n"
" (one + two) != (two + three);\n"
"}");
}
void test7() { // #9335
check("namespace { std::string S = \"\"; }\n"
"\n"
"class C {\n"
"public:\n"
" explicit C(const std::string& s);\n"
"};\n"
"\n"
"void f() {\n"
" for (C c(S); ; ) {\n"
" (void)c;\n"
" }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void test_numeric() {
check("struct P {\n"
" double a;\n"
" double b;\n"
"};\n"
"void f() {\n"
" const P values[2] =\n"
" {\n"
" { 346.1,114.1 }, { 347.1,111.1 }\n"
" };\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void void0() { // #6327
check("void f() { (void*)0; }");
ASSERT_EQUALS("", errout.str());
check("#define X 0\n"
"void f() { X; }");
ASSERT_EQUALS("", errout.str());
}
void intarray() {
check("int arr[] = { 100/2, 1*100 };");
ASSERT_EQUALS("", errout.str());
}
void structarraynull() {
check("struct st arr[] = {\n"
" { 100/2, 1*100 }\n"
" { 90, 70 }\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void structarray() {
check("struct st arr[] = {\n"
" { 100/2, 1*100 }\n"
" { 90, 70 }\n"
"};");
ASSERT_EQUALS("", errout.str());
}
void conditionalcall() {
check("void f() {\n"
" 0==x ? X() : Y();\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void structinit() {
// #2462 - C++11 struct initialization
check("void f() {\n"
" ABC abc{1,2,3};\n"
"}");
ASSERT_EQUALS("", errout.str());
// #6260 - C++11 array initialization
check("void foo() {\n"
" static const char* a[][2] {\n"
" {\"b\", \"\"},\n"
" };\n"
"}");
ASSERT_EQUALS("", errout.str());
// #2482 - false positive for empty struct
check("struct A {};");
ASSERT_EQUALS("", errout.str());
// #4387 - C++11 initializer list
check("A::A() : abc{0} {}");
ASSERT_EQUALS("", errout.str());
// #5042 - C++11 initializer list
check("A::A() : abc::def<int>{0} {}");
ASSERT_EQUALS("", errout.str());
// #4503 - vector init
check("void f() { vector<int> v{1}; }");
ASSERT_EQUALS("", errout.str());
}
void returnstruct() {
check("struct s foo() {\n"
" return (struct s){0,0};\n"
"}");
ASSERT_EQUALS("", errout.str());
// #4754
check("unordered_map<string, string> foo() {\n"
" return {\n"
" {\"hi\", \"there\"},\n"
" {\"happy\", \"sad\"}\n"
" };\n"
"}");
ASSERT_EQUALS("", errout.str());
check("struct s foo() {\n"
" return (struct s){0};\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void cast() {
check("void f() {\n"
" ((struct foo *)(0x1234))->xy = 1;\n"
"}");
ASSERT_EQUALS("", errout.str());
check("bool f(const std::exception& e) {\n" // #10918
" try {\n"
" dynamic_cast<const InvalidTypeException&>(e);\n"
" return true;\n"
" }\n"
" catch (...) {\n"
" return false;\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void increment() {
check("void f() {\n"
" int x = 1;\n"
" x++, x++;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void cpp11init() {
check("void f() {\n"
" int x{1};\n"
"}");
ASSERT_EQUALS("", errout.str());
check("std::vector<int> f(int* p) {\n"
" return std::vector<int>({ p[0] });\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void cpp11init2() {
check("x<string> handlers{\n"
" { \"mode2\", []() { return 2; } },\n"
"};");
ASSERT_EQUALS("", errout.str());
}
void cpp11init3() {
check("struct A { void operator()(int); };\n"
"void f() {\n"
"A{}(0);\n"
"}");
ASSERT_EQUALS("", errout.str());
check("template<class> struct A { void operator()(int); };\n"
"void f() {\n"
"A<int>{}(0);\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void block() {
check("void f() {\n"
" ({ do_something(); 0; });\n"
"}");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
"out:\n"
" ({ do_something(); 0; });\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void mapindex() {
check("void f() {\n"
" map[{\"1\",\"2\"}]=0;\n"
"}");
ASSERT_EQUALS("", errout.str());
}
void commaoperator1() {
check("void foo(int,const char*,int);\n" // #8827
"void f(int value) {\n"
" foo(42,\"test\",42),(value&42);\n"
"}");
ASSERT_EQUALS("[test.cpp:3]: (warning) Found suspicious operator ',', result is not used.\n", errout.str());
check("int f() {\n" // #11257
" int y;\n"
" y = (3, 4);\n"
" return y;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (warning) Found suspicious operator ',', result is not used.\n", errout.str());
}
void commaoperator2() {
check("void f() {\n"
" for(unsigned int a=0, b; a<10; a++ ) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void g();\n" // #10952
"bool f() {\n"
" return (void)g(), false;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int a, int b, int c, int d) {\n"
" Eigen::Vector4d V;\n"
" V << a, b, c, d;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct S { Eigen::Vector4d V; };\n"
"struct T { int a, int b, int c, int d; };\n"
"void f(S& s, const T& t) {\n"
" s.V << t.a, t.b, t.c, t.d;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct S { Eigen::Vector4d V[2]; };\n"
"void f(int a, int b, int c, int d) {\n"
" S s[1];\n"
" s[0].V[1] << a, b, c, d;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n"
" a.b[4][3].c()->d << x , y, z;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct V {\n"
" Eigen::Vector3d& operator[](int i) { return v[i]; }\n"
" void f(int a, int b, int c);\n"
" Eigen::Vector3d v[1];\n"
"};\n"
"void V::f(int a, int b, int c) {\n"
" (*this)[0] << a, b, c;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() {\n" // #11359
" struct S {\n"
" S(int x, int y) {}\n"
" } s(1, 2);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
// #8451
void redundantstmts() {
check("void f1(int x) {\n"
" 1;\n"
" (1);\n"
" (char)1;\n"
" ((char)1);\n"
" !x;\n"
" (!x);\n"
" (unsigned int)!x;\n"
" ~x;\n"
"}\n", true);
ASSERT_EQUALS("[test.cpp:2]: (warning) Redundant code: Found a statement that begins with numeric constant.\n"
"[test.cpp:3]: (warning) Redundant code: Found a statement that begins with numeric constant.\n"
"[test.cpp:4]: (warning) Redundant code: Found a statement that begins with numeric constant.\n"
"[test.cpp:5]: (warning) Redundant code: Found a statement that begins with numeric constant.\n"
"[test.cpp:6]: (warning, inconclusive) Found suspicious operator '!', result is not used.\n"
"[test.cpp:7]: (warning, inconclusive) Found suspicious operator '!', result is not used.\n"
"[test.cpp:8]: (warning) Redundant code: Found unused cast of expression '!x'.\n"
"[test.cpp:9]: (warning, inconclusive) Found suspicious operator '~', result is not used.\n",
errout.str());
check("void f1(int x) { x; }", true);
ASSERT_EQUALS("[test.cpp:1]: (warning) Unused variable value 'x'\n", errout.str());
check("void f() { if (Type t; g(t)) {} }"); // #9776
ASSERT_EQUALS("", errout.str());
check("void f(int x) { static_cast<unsigned>(x); }");
ASSERT_EQUALS("[test.cpp:1]: (warning) Redundant code: Found unused cast of expression 'x'.\n", errout.str());
check("void f(int x, int* p) {\n"
" static_cast<void>(x);\n"
" (void)x;\n"
" static_cast<void*>(p);\n"
" (void*)p;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f() { false; }"); // #10856
ASSERT_EQUALS("[test.cpp:1]: (warning) Redundant code: Found a statement that begins with bool constant.\n", errout.str());
check("void f(int i) {\n"
" (float)(char)i;\n"
" static_cast<float>((char)i);\n"
" (char)static_cast<float>(i);\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2]: (warning) Redundant code: Found unused cast of expression 'i'.\n"
"[test.cpp:3]: (warning) Redundant code: Found unused cast of expression 'i'.\n"
"[test.cpp:4]: (warning) Redundant code: Found unused cast of expression 'i'.\n",
errout.str());
check("namespace M {\n"
" namespace N { typedef char T; }\n"
"}\n"
"void f(int i) {\n"
" (M::N::T)i;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:5]: (warning) Redundant code: Found unused cast of expression 'i'.\n", errout.str());
check("void f(int (g)(int a, int b)) {\n" // #10873
" int p = 0, q = 1;\n"
" (g)(p, q);\n"
"}\n"
"void f() {\n"
" char buf[10];\n"
" (sprintf)(buf, \"%d\", 42);\n"
" (printf)(\"abc\");\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct S; struct T; struct U;\n"
"void f() {\n"
" T t;\n"
" (S)(U)t;\n"
" (S)static_cast<U>(t);\n"
" static_cast<S>((U)t);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(bool b) { b ? true : false; }\n"); // #10865
ASSERT_EQUALS("[test.cpp:1]: (warning) Redundant code: Found unused result of ternary operator.\n", errout.str());
check("struct S { void (*f)() = nullptr; };\n" // #10877
"void g(S* s) {\n"
" (s->f == nullptr) ? nullptr : (s->f(), nullptr);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(bool b) {\n"
" g() ? true : false;\n"
" true ? g() : false;\n"
" false ? true : g();\n"
" g(b ? true : false, 1);\n"
" C c{ b ? true : false, 1 };\n"
" b = (b ? true : false);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int i) {\n"
" for (i; ;) {}\n"
" for ((long)i; ;) {}\n"
" for (1; ;) {}\n"
" for (true; ;) {}\n"
" for ('a'; ;) {}\n"
" for (L'b'; ;) {}\n"
" for (\"x\"; ;) {}\n"
" for (L\"y\"; ;) {}\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2]: (warning) Unused variable value 'i'\n"
"[test.cpp:3]: (warning) Redundant code: Found unused cast of expression 'i'.\n"
"[test.cpp:4]: (warning) Redundant code: Found a statement that begins with numeric constant.\n"
"[test.cpp:5]: (warning) Redundant code: Found a statement that begins with bool constant.\n"
"[test.cpp:6]: (warning) Redundant code: Found a statement that begins with character constant.\n"
"[test.cpp:7]: (warning) Redundant code: Found a statement that begins with character constant.\n"
"[test.cpp:8]: (warning) Redundant code: Found a statement that begins with string constant.\n"
"[test.cpp:9]: (warning) Redundant code: Found a statement that begins with string constant.\n",
errout.str());
check("struct S { bool b{}; };\n"
"struct T {\n"
" S s[2];\n"
" void g();\n"
"};\n"
"void f(const S& r, const S* p) {\n"
" r.b;\n"
" p->b;\n"
" S s;\n"
" (s.b);\n"
" T t, u[2];\n"
" t.s[1].b;\n"
" t.g();\n"
" u[0].g();\n"
" u[1].s[0].b;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:7]: (warning) Redundant code: Found unused member access.\n"
"[test.cpp:8]: (warning) Redundant code: Found unused member access.\n"
"[test.cpp:10]: (warning) Redundant code: Found unused member access.\n"
"[test.cpp:12]: (warning) Redundant code: Found unused member access.\n"
"[test.cpp:15]: (warning) Redundant code: Found unused member access.\n",
errout.str());
check("struct S { int a[2]{}; };\n"
"struct T { S s; };\n"
"void f() {\n"
" int i[2];\n"
" i[0] = 0;\n"
" i[0];\n" // <--
" S s[1];\n"
" s[0].a[1];\n" // <--
" T t;\n"
" t.s.a[1];\n" // <--
" int j[2][2][1] = {};\n"
" j[0][0][0];\n" // <--
"}\n");
ASSERT_EQUALS("[test.cpp:6]: (warning) Redundant code: Found unused array access.\n"
"[test.cpp:8]: (warning) Redundant code: Found unused array access.\n"
"[test.cpp:10]: (warning) Redundant code: Found unused array access.\n"
"[test.cpp:12]: (warning) Redundant code: Found unused array access.\n",
errout.str());
check("void g(std::map<std::string, std::string>& map) {\n"
" int j[2]{};\n"
" int k[2] = {};\n"
" int l[]{ 1, 2 };\n"
" int m[] = { 1, 2 };\n"
" h(0, j[0], 1);\n"
" C c{ 0, j[0], 1 };\n"
" c[0];\n"
" int j[2][2][2] = {};\n"
" j[h()][0][0];\n"
" j[0][h()][0];\n"
" j[0][0][h()];\n"
" std::map<std::string, int> M;\n"
" M[\"abc\"];\n"
" map[\"abc\"];\n" // #10928
" std::auto_ptr<Int> app[4];" // #10919
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct S { void* p; };\n" // #10875
"void f(S s) {\n"
" delete (int*)s.p;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct T {\n" // #10874
" T* p;\n"
"};\n"
"void f(T* t) {\n"
" for (decltype(t->p) (c) = t->p; ;) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int i, std::vector<int*> v);\n" // #10880
"void g() {\n"
" f(1, { static_cast<int*>(nullptr) });\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct S { int i; };\n" // #10882
"enum E {};\n"
"void f(const S* s) {\n"
" E e = (E)!s->i;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(int* p) {\n" // #10932
" int& r(*p[0]);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("struct S { int i; };\n" // #10917
"bool f(S s) {\n"
" return [](int i) { return i > 0; }(s.i);\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("extern int (*p);\n" // #10936
"void f() {\n"
" for (int i = 0; ;) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("class T {};\n" // #10849
"void f() {\n"
" auto g = [](const T* t) -> int {\n"
" const T* u{}, * v{};\n"
" return 0;\n"
" };\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("namespace N {\n" // #10876
" template <class R, class S, void(*T)(R&, float, S)>\n"
" inline void f() {}\n"
" template<class T>\n"
" void g(T& c) {\n"
" for (typename T::iterator v = c.begin(); v != c.end(); ++v) {}\n"
" }\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(std::string a, std::string b) {\n" // #7529
" const std::string s = \" x \" + a;\n"
" +\" y = \" + b;\n"
"}\n", /*inconclusive*/ true);
ASSERT_EQUALS("[test.cpp:3]: (warning, inconclusive) Found suspicious operator '+', result is not used.\n", errout.str());
check("void f() {\n"
" *new int;\n"
"}\n", /*inconclusive*/ true);
ASSERT_EQUALS("[test.cpp:2]: (warning, inconclusive) Found suspicious operator '*', result is not used.\n", errout.str());
check("void f() {\n" // #5475
" std::string(\"a\") + \"a\";\n"
"}\n"
"void f(std::string& a) {\n"
" a.erase(3) + \"suf\";\n"
"}\n", /*inconclusive*/ true);
ASSERT_EQUALS("[test.cpp:2]: (warning, inconclusive) Found suspicious operator '+', result is not used.\n"
"[test.cpp:5]: (warning, inconclusive) Found suspicious operator '+', result is not used.\n",
errout.str());
check("void f(XMLElement& parent) {\n" // #11234
" auto** elem = &parent.firstChild;\n"
"}\n", /*inconclusive*/ true);
ASSERT_EQUALS("", errout.str());
check("void f() {\n" // #11301
" NULL;\n"
" nullptr;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2]: (warning) Redundant code: Found a statement that begins with NULL constant.\n"
"[test.cpp:3]: (warning) Redundant code: Found a statement that begins with NULL constant.\n",
errout.str());
check("struct S { int i; };\n" // #6504
"void f(S* s) {\n"
" (*s).i;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:3]: (warning) Redundant code: Found unused member access.\n", errout.str());
check("int a[2];\n" // #11370
"void f() {\n"
" auto g = [](decltype(a[0]) i) {};\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void vardecl() {
// #8984
check("void f() { a::b *c = d(); }", true);
ASSERT_EQUALS("", errout.str());
check("void f() { std::vector<b> *c; }", true);
ASSERT_EQUALS("", errout.str());
check("void f() { a::b &c = d(); }", true);
ASSERT_EQUALS("", errout.str());
check("void f() { std::vector<b> &c; }", true);
ASSERT_EQUALS("", errout.str());
check("void f() { a::b &&c = d(); }", true);
ASSERT_EQUALS("", errout.str());
check("void f() { std::vector<b> &&c; }", true);
ASSERT_EQUALS("", errout.str());
check("void f() { char * const * a, * const * b; }", true);
ASSERT_EQUALS("", errout.str());
check("void f() { char * const * a = 0, * volatile restrict * b; }", true);
ASSERT_EQUALS("", errout.str());
check("void f() { char * const * a = 0, * volatile const * b; }", true);
ASSERT_EQUALS("", errout.str());
}
void archive() {
check("void f(Archive &ar) {\n"
" ar & x;\n"
"}", true);
ASSERT_EQUALS("", errout.str());
check("void f(int ar) {\n"
" ar & x;\n"
"}", true);
ASSERT_EQUALS("[test.cpp:2]: (warning, inconclusive) Found suspicious operator '&', result is not used.\n", errout.str());
}
void ast() {
check("struct c { void a() const { for (int x=0; x;); } };", true);
ASSERT_EQUALS("", errout.str());
}
void oror() {
check("void foo() {\n"
" params_given (params, \"overrides\") || (overrides = \"1\");\n"
"}", true);
ASSERT_EQUALS("", errout.str());
check("void f(std::ifstream& file) {\n" // #10930
" int a{}, b{};\n"
" (file >> a) || (file >> b);\n"
" (file >> a) && (file >> b);\n"
"}\n", true);
ASSERT_EQUALS("", errout.str());
}
};
REGISTER_TEST(TestIncompleteStatement)
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