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Merged
merged 5 commits into from
May 2, 2019
Merged

CPP: WrongTypeFormatArguments.ql Improvements #1255

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3a0dfbd
CPP: Normalize test cases between some of the WrongTypeFormatArgument…
geoffw0 Apr 15, 2019
98c3e14
CPP: Add test cases of %I64 and similar.
geoffw0 Apr 15, 2019
ac277ad
CPP: Fix %I length specifier.
geoffw0 Apr 15, 2019
a749b5b
CPP: Improve WrongTypeFormatArguments logic when there is more than o…
geoffw0 Apr 15, 2019
1ee28fa
CPP: Add a test cases that uses restrict.
geoffw0 Apr 16, 2019
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8 changes: 5 additions & 3 deletions cpp/ql/src/Likely Bugs/Format/WrongTypeFormatArguments.ql
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Expand Up @@ -25,8 +25,7 @@ private predicate formattingFunctionCallExpectedType(FormattingFunctionCall ffc,
ffc.getTarget() = f and
f.getFormatParameterIndex() = i and
ffc.getArgument(i) = fl and
fl.getConversionType(pos) = expected and
count(fl.getConversionType(pos)) = 1
fl.getConversionType(pos) = expected
)
}

Expand Down Expand Up @@ -143,7 +142,10 @@ from FormattingFunctionCall ffc, int n, Expr arg, Type expected, Type actual
where (
(
formatArgType(ffc, n, expected, arg, actual) and
not trivialConversion(expected.getUnspecifiedType(), actual.getUnspecifiedType())
not exists(Type anyExpected |
formatArgType(ffc, n, anyExpected, arg, actual) and
trivialConversion(anyExpected.getUnspecifiedType(), actual.getUnspecifiedType())
)
)
or
(
Expand Down
4 changes: 2 additions & 2 deletions cpp/ql/src/semmle/code/cpp/commons/Printf.qll
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Expand Up @@ -578,7 +578,7 @@ class FormatLiteral extends Literal {
or ((len="z" or len="Z")
and (result = this.getSize_t() or result = this.getSsize_t()))
or (len="t" and result = this.getPtrdiff_t())
or (len="I" and result instanceof IntType)
or (len="I" and (result = this.getSize_t() or result = this.getPtrdiff_t()))
or (len="I32" and exists(MicrosoftInt32Type t |
t.getUnsigned() = result.(IntegralType).getUnsigned()
))
Expand All @@ -604,7 +604,7 @@ class FormatLiteral extends Literal {
or ((len="z" or len="Z")
and (result = this.getSize_t() or result = this.getSsize_t()))
or (len="t" and result = this.getPtrdiff_t())
or (len="I" and result instanceof IntType)
or (len="I" and (result = this.getSize_t() or result = this.getPtrdiff_t()))
or (len="I32" and exists(MicrosoftInt32Type t |
t.getUnsigned() = result.(IntegralType).getUnsigned()
))
Expand Down
2 changes: 2 additions & 0 deletions ...ormat/WrongTypeFormatArguments/Linux_mixed_byte_wprintf/WrongTypeFormatArguments.expected
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@@ -1,5 +1,7 @@
| tests.cpp:18:15:18:22 | Hello | This argument should be of type 'char *' but is of type 'char16_t *' |
| tests.cpp:19:15:19:22 | Hello | This argument should be of type 'char *' but is of type 'wchar_t *' |
| tests.cpp:21:15:21:21 | Hello | This argument should be of type 'char16_t *' but is of type 'char *' |
| tests.cpp:21:15:21:21 | Hello | This argument should be of type 'wchar_t *' but is of type 'char *' |
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Do you know how this will render in LGTM? One message with two values, or two separate messages on the same line?

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On LGTM it'll be one alert with an expandable placeholder that says [ 2 values ]. Here's an example from a Java query.

| tests.cpp:26:17:26:24 | Hello | This argument should be of type 'char *' but is of type 'char16_t *' |
| tests.cpp:27:17:27:24 | Hello | This argument should be of type 'char *' but is of type 'wchar_t *' |
| tests.cpp:29:17:29:23 | Hello | This argument should be of type 'wchar_t *' but is of type 'char *' |
Expand Down
2 changes: 1 addition & 1 deletion ...uery-tests/Likely Bugs/Format/WrongTypeFormatArguments/Linux_mixed_byte_wprintf/tests.cpp
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Expand Up @@ -18,7 +18,7 @@ void tests() {
printf("%s", u"Hello"); // BAD: expecting char
printf("%s", L"Hello"); // BAD: expecting char

printf("%S", "Hello"); // BAD: expecting wchar_t or char16_t [NOT DETECTED]
printf("%S", "Hello"); // BAD: expecting wchar_t or char16_t
printf("%S", u"Hello"); // GOOD
printf("%S", L"Hello"); // GOOD

Expand Down
2 changes: 2 additions & 0 deletions ...s/Format/WrongTypeFormatArguments/Linux_mixed_word_size/WrongTypeFormatArguments.expected
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@@ -1,2 +1,4 @@
| tests_32.cpp:14:16:14:23 | void_ptr | This argument should be of type 'long' but is of type 'void *' |
| tests_32.cpp:15:15:15:15 | l | This argument should be of type 'void *' but is of type 'long' |
| tests_64.cpp:14:16:14:23 | void_ptr | This argument should be of type 'long' but is of type 'void *' |
| tests_64.cpp:15:15:15:15 | l | This argument should be of type 'void *' but is of type 'long' |
2 changes: 1 addition & 1 deletion ...uery-tests/Likely Bugs/Format/WrongTypeFormatArguments/Linux_mixed_word_size/tests_32.cpp
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Expand Up @@ -12,6 +12,6 @@ void test_32()

printf("%li", l); // GOOD
printf("%li", void_ptr); // BAD
printf("%p", l); // BAD [NOT DETECTED]
printf("%p", l); // BAD
printf("%p", void_ptr); // GOOD
}
2 changes: 1 addition & 1 deletion ...uery-tests/Likely Bugs/Format/WrongTypeFormatArguments/Linux_mixed_word_size/tests_64.cpp
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Expand Up @@ -12,6 +12,6 @@ void test_64()

printf("%li", l); // GOOD
printf("%li", void_ptr); // BAD
printf("%p", l); // BAD [NOT DETECTED]
printf("%p", l); // BAD
printf("%p", void_ptr); // GOOD
}
3 changes: 3 additions & 0 deletions ...Bugs/Format/WrongTypeFormatArguments/Linux_signed_chars/WrongTypeFormatArguments.expected
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@@ -1,6 +1,7 @@
| format.h:16:59:16:61 | str | This argument should be of type 'int' but is of type 'char *' |
| format.h:16:64:16:64 | i | This argument should be of type 'double' but is of type 'int' |
| format.h:16:67:16:67 | d | This argument should be of type 'char *' but is of type 'double' |
| linux_c.c:11:15:11:18 | str3 | This argument should be of type 'char *' but is of type 'short *' |
| pri_macros.h:15:35:15:40 | my_u64 | This argument should be of type 'unsigned int' but is of type 'unsigned long long' |
| printf1.h:12:27:12:27 | i | This argument should be of type 'double' but is of type 'int' |
| printf1.h:18:18:18:18 | i | This argument should be of type 'void *' but is of type 'int' |
Expand All @@ -12,6 +13,8 @@
| printf1.h:46:18:46:20 | ull | This argument should be of type 'unsigned int' but is of type 'unsigned long long' |
| printf1.h:113:17:113:17 | d | This argument should be of type 'long double' but is of type 'double' |
| printf1.h:114:18:114:18 | d | This argument should be of type 'long double' but is of type 'double' |
| printf1.h:147:19:147:19 | i | This argument should be of type 'long long' but is of type 'int' |
| printf1.h:148:19:148:20 | ui | This argument should be of type 'unsigned long long' but is of type 'unsigned int' |
| real_world.h:61:21:61:22 | & ... | This argument should be of type 'int *' but is of type 'short *' |
| real_world.h:62:22:62:23 | & ... | This argument should be of type 'short *' but is of type 'int *' |
| real_world.h:63:22:63:24 | & ... | This argument should be of type 'short *' but is of type 'unsigned int *' |
Expand Down
12 changes: 12 additions & 0 deletions ...test/query-tests/Likely Bugs/Format/WrongTypeFormatArguments/Linux_signed_chars/linux_c.c
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@@ -0,0 +1,12 @@
/** standard printf functions */

int printf(const char *format, ...);

/** test program */

void restrict_cases(char * restrict str1, const char * restrict str2, short * restrict str3)
{
printf("%s", str1); // GOOD
printf("%s", str2); // GOOD
printf("%s", str3); // BAD
}
2 changes: 1 addition & 1 deletion ...l/test/query-tests/Likely Bugs/Format/WrongTypeFormatArguments/Linux_signed_chars/options
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@@ -1 +1 @@
semmle-extractor-options: --edg --signed_chars
semmle-extractor-options: --clang --edg --signed_chars
17 changes: 17 additions & 0 deletions ...test/query-tests/Likely Bugs/Format/WrongTypeFormatArguments/Linux_signed_chars/printf1.h
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Expand Up @@ -134,3 +134,20 @@ void extensions()
printf("%llu", uli); // BAD (should be %lu) [NOT DETECTED]
}
}

void fun4()
{
int i;
unsigned int ui;
long l;
unsigned long ul;
long long ll;
unsigned long long ull;

printf("%qi\n", i); // BAD
printf("%qu\n", ui); // BAD
printf("%qi\n", l); // GOOD
printf("%qu\n", ul); // GOOD
printf("%qi\n", ll); // GOOD
printf("%qu\n", ull); // GOOD
}
7 changes: 5 additions & 2 deletions ...gs/Format/WrongTypeFormatArguments/Linux_unsigned_chars/WrongTypeFormatArguments.expected
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Expand Up @@ -10,8 +10,11 @@
| printf1.h:44:18:44:20 | ull | This argument should be of type 'int' but is of type 'unsigned long long' |
| printf1.h:45:18:45:20 | ull | This argument should be of type 'unsigned int' but is of type 'unsigned long long' |
| printf1.h:46:18:46:20 | ull | This argument should be of type 'unsigned int' but is of type 'unsigned long long' |
| printf1.h:126:18:126:19 | wc | This argument should be of type 'char *' but is of type 'wchar_t *' |
| printf1.h:127:18:127:18 | c | This argument should be of type 'wchar_t *' but is of type 'char *' |
| printf1.h:130:18:130:18 | 0 | This argument should be of type 'void *' but is of type 'int' |
| printf1.h:154:18:154:19 | wc | This argument should be of type 'char *' but is of type 'wchar_t *' |
| printf1.h:155:18:155:18 | c | This argument should be of type 'wchar_t *' but is of type 'char *' |
| printf1.h:168:19:168:19 | i | This argument should be of type 'long long' but is of type 'int' |
| printf1.h:169:19:169:20 | ui | This argument should be of type 'unsigned long long' but is of type 'unsigned int' |
| real_world.h:61:21:61:22 | & ... | This argument should be of type 'int *' but is of type 'short *' |
| real_world.h:62:22:62:23 | & ... | This argument should be of type 'short *' but is of type 'int *' |
| real_world.h:63:22:63:24 | & ... | This argument should be of type 'short *' but is of type 'unsigned int *' |
Expand Down
45 changes: 45 additions & 0 deletions ...st/query-tests/Likely Bugs/Format/WrongTypeFormatArguments/Linux_unsigned_chars/printf1.h
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Expand Up @@ -102,6 +102,34 @@ void fun1(unsigned char* a, unsigned char* b) {
printf("%td\n", a-b); // GOOD
}

typedef wchar_t WCHAR_T; // WCHAR_T -> wchar_t -> int
typedef int MYCHAR; // MYCHAR -> int (notably not via the wchar_t typedef)

void fun2() {
wchar_t *myString1;
WCHAR_T *myString2;
int *myString3;
MYCHAR *myString4;

printf("%S", myString1); // GOOD
printf("%S", myString2); // GOOD
printf("%S", myString3); // GOOD
printf("%S", myString4); // GOOD
}

typedef void *VOIDPTR;
typedef int (*FUNPTR)(int);

void fun3(void *p1, VOIDPTR p2, FUNPTR p3, char *p4)
{
printf("%p\n", p1); // GOOD
printf("%p\n", p2); // GOOD
printf("%p\n", p3); // GOOD
printf("%p\n", p4); // GOOD
printf("%p\n", p4 + 1); // GOOD
printf("%p\n", 0); // GOOD [FALSE POSITIVE]
}

typedef unsigned int wint_t;

void test_chars(char c, wchar_t wc, wint_t wt)
Expand All @@ -127,3 +155,20 @@ void test_ws(char *c, wchar_t *wc)
wprintf(L"%S", c); // BAD
wprintf(L"%S", wc); // GOOD
}

void fun4()
{
int i;
unsigned int ui;
long l;
unsigned long ul;
long long ll;
unsigned long long ull;

printf("%qi\n", i); // BAD
printf("%qu\n", ui); // BAD
printf("%qi\n", l); // GOOD
printf("%qu\n", ul); // GOOD
printf("%qi\n", ll); // GOOD
printf("%qu\n", ull); // GOOD
}
17 changes: 15 additions & 2 deletions ...s/Likely Bugs/Format/WrongTypeFormatArguments/Microsoft/WrongTypeFormatArguments.expected
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Expand Up @@ -16,8 +16,21 @@
| printf1.h:74:19:74:22 | C_ST | This argument should be of type 'ssize_t' but is of type 'unsigned long long' |
| printf1.h:75:19:75:28 | sizeof(<expr>) | This argument should be of type 'ssize_t' but is of type 'unsigned long long' |
| printf1.h:84:23:84:35 | ... - ... | This argument should be of type 'ssize_t' but is of type 'long long' |
| printf1.h:125:18:125:18 | c | This argument should be of type '__wchar_t *' but is of type 'char *' |
| printf1.h:128:18:128:19 | wc | This argument should be of type 'char *' but is of type '__wchar_t *' |
| printf1.h:116:16:116:24 | myString3 | This argument should be of type '__wchar_t *' but is of type 'int *' |
| printf1.h:117:16:117:24 | myString4 | This argument should be of type '__wchar_t *' but is of type 'int *' |
| printf1.h:130:18:130:18 | 0 | This argument should be of type 'void *' but is of type 'int' |
| printf1.h:153:18:153:18 | c | This argument should be of type '__wchar_t *' but is of type 'char *' |
| printf1.h:156:18:156:19 | wc | This argument should be of type 'char *' but is of type '__wchar_t *' |
| printf1.h:181:21:181:22 | ll | This argument should be of type 'int' but is of type 'long long' |
| printf1.h:182:21:182:23 | ull | This argument should be of type 'unsigned int' but is of type 'unsigned long long' |
| printf1.h:185:21:185:23 | i64 | This argument should be of type 'int' but is of type 'long long' |
| printf1.h:186:21:186:23 | u64 | This argument should be of type 'unsigned int' but is of type 'unsigned long long' |
| printf1.h:188:21:188:21 | i | This argument should be of type 'long long' but is of type 'int' |
| printf1.h:189:21:189:22 | ui | This argument should be of type 'unsigned long long' but is of type 'unsigned int' |
| printf1.h:190:21:190:21 | l | This argument should be of type 'long long' but is of type 'long' |
| printf1.h:191:21:191:22 | ul | This argument should be of type 'unsigned long long' but is of type 'unsigned long' |
| printf1.h:194:21:194:23 | i32 | This argument should be of type 'long long' but is of type 'int' |
| printf1.h:195:21:195:23 | u32 | This argument should be of type 'unsigned long long' but is of type 'unsigned int' |
| real_world.h:61:21:61:22 | & ... | This argument should be of type 'int *' but is of type 'short *' |
| real_world.h:62:22:62:23 | & ... | This argument should be of type 'short *' but is of type 'int *' |
| real_world.h:63:22:63:24 | & ... | This argument should be of type 'short *' but is of type 'unsigned int *' |
Expand Down
69 changes: 69 additions & 0 deletions cpp/ql/test/query-tests/Likely Bugs/Format/WrongTypeFormatArguments/Microsoft/printf1.h
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Expand Up @@ -102,6 +102,34 @@ void fun1(unsigned char* a, unsigned char* b) {
printf("%td\n", a-b); // GOOD
}

typedef wchar_t WCHAR_T; // WCHAR_T -> wchar_t
typedef int MYCHAR; // MYCHAR -> int

void fun2() {
wchar_t *myString1;
WCHAR_T *myString2;
int *myString3;
MYCHAR *myString4;

printf("%S", myString1); // GOOD
printf("%S", myString2); // GOOD
printf("%S", myString3); // BAD
printf("%S", myString4); // BAD
}

typedef void *VOIDPTR;
typedef int (*FUNPTR)(int);

void fun3(void *p1, VOIDPTR p2, FUNPTR p3, char *p4)
{
printf("%p\n", p1); // GOOD
printf("%p\n", p2); // GOOD
printf("%p\n", p3); // GOOD
printf("%p\n", p4); // GOOD
printf("%p\n", p4 + 1); // GOOD
printf("%p\n", 0); // GOOD [FALSE POSITIVE]
}

typedef unsigned int wint_t;

void test_chars(char c, wchar_t wc, wint_t wt)
Expand All @@ -127,3 +155,44 @@ void test_ws(char *c, wchar_t *wc, wint_t *wt)
wprintf(L"%S", c); // GOOD
wprintf(L"%S", wc); // BAD
}

void fun4()
{
ptrdiff_t pdt;
size_t sz;
int i;
unsigned int ui;
long l;
unsigned long ul;
long long ll;
unsigned long long ull;
__int32 i32;
unsigned __int32 u32;
__int64 i64;
unsigned __int64 u64;

printf("%Ii\n", pdt); // GOOD
printf("%Iu\n", sz); // GOOD

printf("%I32i\n", i); // GOOD
printf("%I32u\n", ui); // GOOD
printf("%I32i\n", l); // GOOD
printf("%I32u\n", ul); // GOOD
printf("%I32i\n", ll); // BAD
printf("%I32u\n", ull); // BAD
printf("%I32i\n", i32); // GOOD
printf("%I32u\n", u32); // GOOD
printf("%I32i\n", i64); // BAD
printf("%I32u\n", u64); // BAD

printf("%I64i\n", i); // BAD
printf("%I64u\n", ui); // BAD
printf("%I64i\n", l); // BAD
printf("%I64u\n", ul); // BAD
printf("%I64i\n", ll); // GOOD
printf("%I64u\n", ull); // GOOD
printf("%I64i\n", i32); // BAD
printf("%I64u\n", u32); // BAD
printf("%I64i\n", i64); // GOOD
printf("%I64u\n", u64); // GOOD
}
11 changes: 11 additions & 0 deletions ...Bugs/Format/WrongTypeFormatArguments/Microsoft_no_wchar/WrongTypeFormatArguments.expected
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Expand Up @@ -17,8 +17,19 @@
| printf1.h:75:19:75:28 | sizeof(<expr>) | This argument should be of type 'ssize_t' but is of type 'unsigned long long' |
| printf1.h:84:23:84:35 | ... - ... | This argument should be of type 'ssize_t' but is of type 'long long' |
| printf1.h:130:18:130:18 | 0 | This argument should be of type 'void *' but is of type 'int' |
| printf1.h:155:21:155:22 | ll | This argument should be of type 'int' but is of type 'long long' |
| printf1.h:156:21:156:23 | ull | This argument should be of type 'unsigned int' but is of type 'unsigned long long' |
| printf1.h:159:21:159:23 | i64 | This argument should be of type 'int' but is of type 'long long' |
| printf1.h:160:21:160:23 | u64 | This argument should be of type 'unsigned int' but is of type 'unsigned long long' |
| printf1.h:162:21:162:21 | i | This argument should be of type 'long long' but is of type 'int' |
| printf1.h:163:21:163:22 | ui | This argument should be of type 'unsigned long long' but is of type 'unsigned int' |
| printf1.h:164:21:164:21 | l | This argument should be of type 'long long' but is of type 'long' |
| printf1.h:165:21:165:22 | ul | This argument should be of type 'unsigned long long' but is of type 'unsigned long' |
| printf1.h:168:21:168:23 | i32 | This argument should be of type 'long long' but is of type 'int' |
| printf1.h:169:21:169:23 | u32 | This argument should be of type 'unsigned long long' but is of type 'unsigned int' |
| real_world.h:61:21:61:22 | & ... | This argument should be of type 'int *' but is of type 'short *' |
| real_world.h:62:22:62:23 | & ... | This argument should be of type 'short *' but is of type 'int *' |
| real_world.h:63:22:63:24 | & ... | This argument should be of type 'short *' but is of type 'unsigned int *' |
| real_world.h:64:22:64:24 | & ... | This argument should be of type 'short *' but is of type 'signed int *' |
| wide_string.h:25:18:25:20 | c | This argument should be of type 'char' but is of type 'char *' |
| wide_string.h:29:19:29:22 | c | This argument should be of type 'wchar_t' but is of type 'unsigned short *' |
41 changes: 41 additions & 0 deletions ...test/query-tests/Likely Bugs/Format/WrongTypeFormatArguments/Microsoft_no_wchar/printf1.h
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Expand Up @@ -129,3 +129,44 @@ void fun3(void *p1, VOIDPTR p2, FUNPTR p3, char *p4)
printf("%p\n", p4 + 1); // GOOD
printf("%p\n", 0); // GOOD [FALSE POSITIVE]
}

void fun4()
{
ptrdiff_t pdt;
size_t sz;
int i;
unsigned int ui;
long l;
unsigned long ul;
long long ll;
unsigned long long ull;
__int32 i32;
unsigned __int32 u32;
__int64 i64;
unsigned __int64 u64;

printf("%Ii\n", pdt); // GOOD
printf("%Iu\n", sz); // GOOD

printf("%I32i\n", i); // GOOD
printf("%I32u\n", ui); // GOOD
printf("%I32i\n", l); // GOOD
printf("%I32u\n", ul); // GOOD
printf("%I32i\n", ll); // BAD
printf("%I32u\n", ull); // BAD
printf("%I32i\n", i32); // GOOD
printf("%I32u\n", u32); // GOOD
printf("%I32i\n", i64); // BAD
printf("%I32u\n", u64); // BAD

printf("%I64i\n", i); // BAD
printf("%I64u\n", ui); // BAD
printf("%I64i\n", l); // BAD
printf("%I64u\n", ul); // BAD
printf("%I64i\n", ll); // GOOD
printf("%I64u\n", ull); // GOOD
printf("%I64i\n", i32); // BAD
printf("%I64u\n", u32); // BAD
printf("%I64i\n", i64); // GOOD
printf("%I64u\n", u64); // GOOD
}
2 changes: 1 addition & 1 deletion .../query-tests/Likely Bugs/Format/WrongTypeFormatArguments/Microsoft_no_wchar/wide_string.h
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Expand Up @@ -26,5 +26,5 @@ void test_wchar4(char c, const char cc, wchar_t wc, const wchar_t wcc) {
printf("%wc", wc); // GOOD
printf("%wc", wcc); // GOOD
printf("%wc", L'c'); // GOOD
printf("%wc", L"c"); // BAD [NOT DETECTED]
printf("%wc", L"c"); // BAD
}