// RUN: %clang_cc1 -fsyntax-only -verify -Wformat-nonliteral -isystem %S/Inputs %s // RUN: %clang_cc1 -fsyntax-only -verify -Wformat-nonliteral -isystem %S/Inputs -fno-signed-char %s #define __need_wint_t #include <stdarg.h> #include <stddef.h> // For wint_t and wchar_t typedef struct _FILE FILE; int fprintf(FILE *, const char *restrict, ...); int printf(const char *restrict, ...); // expected-note{{passing argument to parameter here}} int snprintf(char *restrict, size_t, const char *restrict, ...); int sprintf(char *restrict, const char *restrict, ...); int vasprintf(char **, const char *, va_list); int asprintf(char **, const char *, ...); int vfprintf(FILE *, const char *restrict, va_list); int vprintf(const char *restrict, va_list); int vsnprintf(char *, size_t, const char *, va_list); int vsprintf(char *restrict, const char *restrict, va_list); // expected-note{{passing argument to parameter here}} int vscanf(const char *restrict format, va_list arg); char * global_fmt; void check_string_literal( FILE* fp, const char* s, char *buf, ... ) { char * b; va_list ap; va_start(ap,buf); printf(s); // expected-warning {{format string is not a string literal}} vprintf(s,ap); // expected-warning {{format string is not a string literal}} fprintf(fp,s); // expected-warning {{format string is not a string literal}} vfprintf(fp,s,ap); // expected-warning {{format string is not a string literal}} asprintf(&b,s); // expected-warning {{format string is not a string lit}} vasprintf(&b,s,ap); // expected-warning {{format string is not a string literal}} sprintf(buf,s); // expected-warning {{format string is not a string literal}} snprintf(buf,2,s); // expected-warning {{format string is not a string lit}} __builtin___sprintf_chk(buf,0,-1,s); // expected-warning {{format string is not a string literal}} __builtin___snprintf_chk(buf,2,0,-1,s); // expected-warning {{format string is not a string lit}} vsprintf(buf,s,ap); // expected-warning {{format string is not a string lit}} vsnprintf(buf,2,s,ap); // expected-warning {{format string is not a string lit}} vsnprintf(buf,2,global_fmt,ap); // expected-warning {{format string is not a string literal}} __builtin___vsnprintf_chk(buf,2,0,-1,s,ap); // expected-warning {{format string is not a string lit}} __builtin___vsnprintf_chk(buf,2,0,-1,global_fmt,ap); // expected-warning {{format string is not a string literal}} vscanf(s, ap); // expected-warning {{format string is not a string literal}} // rdar://6079877 printf("abc" "%*d", 1, 1); // no-warning printf("abc\ def" "%*d", 1, 1); // no-warning // <rdar://problem/6079850>, allow 'unsigned' (instead of 'int') to be used for both // the field width and precision. This deviates from C99, but is reasonably safe // and is also accepted by GCC. printf("%*d", (unsigned) 1, 1); // no-warning } __attribute__((__format__ (__printf__, 2, 4))) void check_string_literal2( FILE* fp, const char* s, char *buf, ... ) { char * b; va_list ap; va_start(ap,buf); printf(s); // expected-warning {{format string is not a string literal}} vprintf(s,ap); // no-warning fprintf(fp,s); // expected-warning {{format string is not a string literal}} vfprintf(fp,s,ap); // no-warning asprintf(&b,s); // expected-warning {{format string is not a string lit}} vasprintf(&b,s,ap); // no-warning sprintf(buf,s); // expected-warning {{format string is not a string literal}} snprintf(buf,2,s); // expected-warning {{format string is not a string lit}} __builtin___vsnprintf_chk(buf,2,0,-1,s,ap); // no-warning vscanf(s, ap); // expected-warning {{format string is not a string literal}} } void check_conditional_literal(const char* s, int i) { printf(i == 1 ? "yes" : "no"); // no-warning printf(i == 0 ? (i == 1 ? "yes" : "no") : "dont know"); // no-warning printf(i == 0 ? (i == 1 ? s : "no") : "dont know"); // expected-warning{{format string is not a string literal}} printf("yes" ?: "no %d", 1); // expected-warning{{data argument not used by format string}} } void check_writeback_specifier() { int x; char *b; printf("%n", b); // expected-warning{{format specifies type 'int *' but the argument has type 'char *'}} printf("%n", &x); // no-warning printf("%hhn", (signed char*)0); // no-warning printf("%hhn", (char*)0); // no-warning printf("%hhn", (unsigned char*)0); // no-warning printf("%hhn", (int*)0); // expected-warning{{format specifies type 'signed char *' but the argument has type 'int *'}} printf("%hn", (short*)0); // no-warning printf("%hn", (unsigned short*)0); // no-warning printf("%hn", (int*)0); // expected-warning{{format specifies type 'short *' but the argument has type 'int *'}} printf("%n", (int*)0); // no-warning printf("%n", (unsigned int*)0); // no-warning printf("%n", (char*)0); // expected-warning{{format specifies type 'int *' but the argument has type 'char *'}} printf("%ln", (long*)0); // no-warning printf("%ln", (unsigned long*)0); // no-warning printf("%ln", (int*)0); // expected-warning{{format specifies type 'long *' but the argument has type 'int *'}} printf("%lln", (long long*)0); // no-warning printf("%lln", (unsigned long long*)0); // no-warning printf("%lln", (int*)0); // expected-warning{{format specifies type 'long long *' but the argument has type 'int *'}} printf("%qn", (long long*)0); // no-warning printf("%qn", (unsigned long long*)0); // no-warning printf("%qn", (int*)0); // expected-warning{{format specifies type 'long long *' but the argument has type 'int *'}} printf("%Ln", 0); // expected-warning{{length modifier 'L' results in undefined behavior or no effect with 'n' conversion specifier}} // expected-note@-1{{did you mean to use 'll'?}} } void check_invalid_specifier(FILE* fp, char *buf) { printf("%s%lb%d","unix",10,20); // expected-warning {{invalid conversion specifier 'b'}} fprintf(fp,"%%%l"); // expected-warning {{incomplete format specifier}} sprintf(buf,"%%%%%ld%d%d", 1, 2, 3); // expected-warning{{format specifies type 'long' but the argument has type 'int'}} snprintf(buf, 2, "%%%%%ld%;%d", 1, 2, 3); // expected-warning{{format specifies type 'long' but the argument has type 'int'}} expected-warning {{invalid conversion specifier ';'}} } void check_null_char_string(char* b) { printf("\0this is bogus%d",1); // expected-warning {{string contains '\0'}} snprintf(b,10,"%%%%%d\0%d",1,2); // expected-warning {{string contains '\0'}} printf("%\0d",1); // expected-warning {{string contains '\0'}} } void check_empty_format_string(char* buf, ...) { va_list ap; va_start(ap,buf); vprintf("",ap); // expected-warning {{format string is empty}} sprintf(buf, "", 1); // expected-warning {{format string is empty}} // Don't warn about empty format strings when there are no data arguments. // This can arise from macro expansions and non-standard format string // functions. sprintf(buf, ""); // no-warning } void check_wide_string(char* b, ...) { va_list ap; va_start(ap,b); printf(L"foo %d",2); // expected-warning {{incompatible pointer types}}, expected-warning {{should not be a wide string}} vsprintf(b,L"bar %d",ap); // expected-warning {{incompatible pointer types}}, expected-warning {{should not be a wide string}} } void check_asterisk_precision_width(int x) { printf("%*d"); // expected-warning {{'*' specified field width is missing a matching 'int' argument}} printf("%.*d"); // expected-warning {{'.*' specified field precision is missing a matching 'int' argument}} printf("%*d",12,x); // no-warning printf("%*d","foo",x); // expected-warning {{field width should have type 'int', but argument has type 'char *'}} printf("%.*d","foo",x); // expected-warning {{field precision should have type 'int', but argument has type 'char *'}} } void __attribute__((format(printf,1,3))) myprintf(const char*, int blah, ...); void test_myprintf() { myprintf("%d", 17, 18); // okay } void test_constant_bindings(void) { const char * const s1 = "hello"; const char s2[] = "hello"; const char *s3 = "hello"; char * const s4 = "hello"; extern const char s5[]; printf(s1); // no-warning printf(s2); // no-warning printf(s3); // expected-warning{{not a string literal}} printf(s4); // expected-warning{{not a string literal}} printf(s5); // expected-warning{{not a string literal}} } // Test what happens when -Wformat-security only. #pragma GCC diagnostic ignored "-Wformat-nonliteral" #pragma GCC diagnostic warning "-Wformat-security" void test9(char *P) { int x; printf(P); // expected-warning {{format string is not a string literal (potentially insecure)}} printf(P, 42); } void torture(va_list v8) { vprintf ("%*.*d", v8); // no-warning } void test10(int x, float f, int i, long long lli) { printf("%s"); // expected-warning{{more '%' conversions than data arguments}} printf("%@", 12); // expected-warning{{invalid conversion specifier '@'}} printf("\0"); // expected-warning{{format string contains '\0' within the string body}} printf("xs\0"); // expected-warning{{format string contains '\0' within the string body}} printf("%*d\n"); // expected-warning{{'*' specified field width is missing a matching 'int' argument}} printf("%*.*d\n", x); // expected-warning{{'.*' specified field precision is missing a matching 'int' argument}} printf("%*d\n", f, x); // expected-warning{{field width should have type 'int', but argument has type 'double'}} printf("%*.*d\n", x, f, x); // expected-warning{{field precision should have type 'int', but argument has type 'double'}} printf("%**\n"); // expected-warning{{invalid conversion specifier '*'}} printf("%d%d\n", x); // expected-warning{{more '%' conversions than data arguments}} printf("%d\n", x, x); // expected-warning{{data argument not used by format string}} printf("%W%d%Z\n", x, x, x); // expected-warning{{invalid conversion specifier 'W'}} expected-warning{{invalid conversion specifier 'Z'}} printf("%"); // expected-warning{{incomplete format specifier}} printf("%.d", x); // no-warning printf("%.", x); // expected-warning{{incomplete format specifier}} printf("%f", 4); // expected-warning{{format specifies type 'double' but the argument has type 'int'}} printf("%qd", lli); // no-warning printf("%qd", x); // expected-warning{{format specifies type 'long long' but the argument has type 'int'}} printf("%qp", (void *)0); // expected-warning{{length modifier 'q' results in undefined behavior or no effect with 'p' conversion specifier}} printf("hhX %hhX", (unsigned char)10); // no-warning printf("llX %llX", (long long) 10); // no-warning // This is fine, because there is an implicit conversion to an int. printf("%d", (unsigned char) 10); // no-warning printf("%d", (long long) 10); // expected-warning{{format specifies type 'int' but the argument has type 'long long'}} printf("%Lf\n", (long double) 1.0); // no-warning printf("%f\n", (long double) 1.0); // expected-warning{{format specifies type 'double' but the argument has type 'long double'}} // The man page says that a zero precision is okay. printf("%.0Lf", (long double) 1.0); // no-warning printf("%c\n", "x"); // expected-warning{{format specifies type 'int' but the argument has type 'char *'}} printf("%c\n", 1.23); // expected-warning{{format specifies type 'int' but the argument has type 'double'}} printf("Format %d, is %! %f", 1, 2, 4.4); // expected-warning{{invalid conversion specifier '!'}} } typedef unsigned char uint8_t; void should_understand_small_integers() { printf("%hhu", (short) 10); // expected-warning{{format specifies type 'unsigned char' but the argument has type 'short'}} printf("%hu\n", (unsigned char) 1); // expected-warning{{format specifies type 'unsigned short' but the argument has type 'unsigned char'}} printf("%hu\n", (uint8_t)1); // expected-warning{{format specifies type 'unsigned short' but the argument has type 'uint8_t'}} } void test11(void *p, char *s) { printf("%p", p); // no-warning printf("%p", 123); // expected-warning{{format specifies type 'void *' but the argument has type 'int'}} printf("%.4p", p); // expected-warning{{precision used with 'p' conversion specifier, resulting in undefined behavior}} printf("%+p", p); // expected-warning{{flag '+' results in undefined behavior with 'p' conversion specifier}} printf("% p", p); // expected-warning{{flag ' ' results in undefined behavior with 'p' conversion specifier}} printf("%0p", p); // expected-warning{{flag '0' results in undefined behavior with 'p' conversion specifier}} printf("%s", s); // no-warning printf("%+s", p); // expected-warning{{flag '+' results in undefined behavior with 's' conversion specifier}} printf("% s", p); // expected-warning{{flag ' ' results in undefined behavior with 's' conversion specifier}} printf("%0s", p); // expected-warning{{flag '0' results in undefined behavior with 's' conversion specifier}} } void test12(char *b) { unsigned char buf[4]; printf ("%.4s\n", buf); // no-warning printf ("%.4s\n", &buf); // expected-warning{{format specifies type 'char *' but the argument has type 'unsigned char (*)[4]'}} // Verify that we are checking asprintf asprintf(&b, "%d", "asprintf"); // expected-warning{{format specifies type 'int' but the argument has type 'char *'}} } void test13(short x) { char bel = 007; printf("bel: '0%hhd'\n", bel); // no-warning printf("x: '0%hhd'\n", x); // expected-warning {{format specifies type 'char' but the argument has type 'short'}} } typedef struct __aslclient *aslclient; typedef struct __aslmsg *aslmsg; int asl_log(aslclient asl, aslmsg msg, int level, const char *format, ...) __attribute__((__format__ (__printf__, 4, 5))); void test_asl(aslclient asl) { // Test case from <rdar://problem/7341605>. asl_log(asl, 0, 3, "Error: %m"); // no-warning asl_log(asl, 0, 3, "Error: %W"); // expected-warning{{invalid conversion specifier 'W'}} } // <rdar://problem/7595366> typedef enum { A } int_t; void f0(int_t x) { printf("%d\n", x); } // Unicode test cases. These are possibly specific to Mac OS X. If so, they should // eventually be moved into a separate test. void test_unicode_conversions(wchar_t *s) { printf("%S", s); // no-warning printf("%s", s); // expected-warning{{format specifies type 'char *' but the argument has type 'wchar_t *'}} printf("%C", s[0]); // no-warning printf("%c", s[0]); // FIXME: This test reports inconsistent results. On Windows, '%C' expects // 'unsigned short'. // printf("%C", 10); printf("%S", "hello"); // expected-warning{{but the argument has type 'char *'}} } // Mac OS X supports positional arguments in format strings. // This is an IEEE extension (IEEE Std 1003.1). // FIXME: This is probably not portable everywhere. void test_positional_arguments() { printf("%0$", (int)2); // expected-warning{{position arguments in format strings start counting at 1 (not 0)}} printf("%1$*0$d", (int) 2); // expected-warning{{position arguments in format strings start counting at 1 (not 0)}} printf("%1$d", (int) 2); // no-warning printf("%1$d", (int) 2, 2); // expected-warning{{data argument not used by format string}} printf("%1$d%1$f", (int) 2); // expected-warning{{format specifies type 'double' but the argument has type 'int'}} printf("%1$2.2d", (int) 2); // no-warning printf("%2$*1$.2d", (int) 2, (int) 3); // no-warning printf("%2$*8$d", (int) 2, (int) 3); // expected-warning{{specified field width is missing a matching 'int' argument}} printf("%%%1$d", (int) 2); // no-warning printf("%1$d%%", (int) 2); // no-warning } // PR 6697 - Handle format strings where the data argument is not adjacent to the format string void myprintf_PR_6697(const char *format, int x, ...) __attribute__((__format__(printf,1, 3))); void test_pr_6697() { myprintf_PR_6697("%s\n", 1, "foo"); // no-warning myprintf_PR_6697("%s\n", 1, (int)0); // expected-warning{{format specifies type 'char *' but the argument has type 'int'}} // FIXME: Not everything should clearly support positional arguments, // but we need a way to identify those cases. myprintf_PR_6697("%1$s\n", 1, "foo"); // no-warning myprintf_PR_6697("%2$s\n", 1, "foo"); // expected-warning{{data argument position '2' exceeds the number of data arguments (1)}} myprintf_PR_6697("%18$s\n", 1, "foo"); // expected-warning{{data argument position '18' exceeds the number of data arguments (1)}} myprintf_PR_6697("%1$s\n", 1, (int) 0); // expected-warning{{format specifies type 'char *' but the argument has type 'int'}} } void rdar8026030(FILE *fp) { fprintf(fp, "\%"); // expected-warning{{incomplete format specifier}} } void bug7377_bad_length_mod_usage() { // Bad length modifiers printf("%hhs", "foo"); // expected-warning{{length modifier 'hh' results in undefined behavior or no effect with 's' conversion specifier}} printf("%1$zp", (void *)0); // expected-warning{{length modifier 'z' results in undefined behavior or no effect with 'p' conversion specifier}} printf("%ls", L"foo"); // no-warning printf("%#.2Lf", (long double)1.234); // no-warning // Bad flag usage printf("%#p", (void *) 0); // expected-warning{{flag '#' results in undefined behavior with 'p' conversion specifier}} printf("%0d", -1); // no-warning printf("%#n", (int *) 0); // expected-warning{{flag '#' results in undefined behavior with 'n' conversion specifier}} printf("%-n", (int *) 0); // expected-warning{{flag '-' results in undefined behavior with 'n' conversion specifier}} printf("%-p", (void *) 0); // no-warning // Bad optional amount use printf("%.2c", 'a'); // expected-warning{{precision used with 'c' conversion specifier, resulting in undefined behavior}} printf("%1n", (int *) 0); // expected-warning{{field width used with 'n' conversion specifier, resulting in undefined behavior}} printf("%.9n", (int *) 0); // expected-warning{{precision used with 'n' conversion specifier, resulting in undefined behavior}} // Ignored flags printf("% +f", 1.23); // expected-warning{{flag ' ' is ignored when flag '+' is present}} printf("%+ f", 1.23); // expected-warning{{flag ' ' is ignored when flag '+' is present}} printf("%0-f", 1.23); // expected-warning{{flag '0' is ignored when flag '-' is present}} printf("%-0f", 1.23); // expected-warning{{flag '0' is ignored when flag '-' is present}} printf("%-+f", 1.23); // no-warning } // PR 7981 - handle '%lc' (wint_t) void pr7981(wint_t c, wchar_t c2) { printf("%lc", c); // no-warning printf("%lc", 1.0); // expected-warning{{the argument has type 'double'}} printf("%lc", (char) 1); // no-warning printf("%lc", &c); // expected-warning{{the argument has type 'wint_t *'}} // If wint_t and wchar_t are the same width and wint_t is signed where // wchar_t is unsigned, an implicit conversion isn't possible. #if defined(__WINT_UNSIGNED__) || !defined(__WCHAR_UNSIGNED__) || \ __WINT_WIDTH__ > __WCHAR_WIDTH__ printf("%lc", c2); // no-warning #endif } // <rdar://problem/8269537> -Wformat-security says NULL is not a string literal void rdar8269537() { // This is likely to crash in most cases, but -Wformat-nonliteral technically // doesn't warn in this case. printf(0); // no-warning } // Handle functions with multiple format attributes. extern void rdar8332221_vprintf_scanf(const char *, va_list, const char *, ...) __attribute__((__format__(__printf__, 1, 0))) __attribute__((__format__(__scanf__, 3, 4))); void rdar8332221(va_list ap, int *x, long *y) { rdar8332221_vprintf_scanf("%", ap, "%d", x); // expected-warning{{incomplete format specifier}} } // PR8641 void pr8641() { printf("%#x\n", 10); printf("%#X\n", 10); } void posix_extensions() { // Test %'d, "thousands grouping". // <rdar://problem/8816343> printf("%'d\n", 123456789); // no-warning printf("%'i\n", 123456789); // no-warning printf("%'f\n", (float) 1.0); // no-warning printf("%'p\n", (void*) 0); // expected-warning{{results in undefined behavior with 'p' conversion specifier}} } // PR8486 // // Test what happens when -Wformat is on, but -Wformat-security is off. #pragma GCC diagnostic warning "-Wformat" #pragma GCC diagnostic ignored "-Wformat-security" void pr8486() { printf("%s", 1); // expected-warning{{format specifies type 'char *' but the argument has type 'int'}} } // PR9314 // Don't warn about string literals that are PreDefinedExprs, e.g. __func__. void pr9314() { printf(__PRETTY_FUNCTION__); // no-warning printf(__func__); // no-warning } int printf(const char * restrict, ...) __attribute__((__format__ (__printf__, 1, 2))); void rdar9612060(void) { printf("%s", 2); // expected-warning{{format specifies type 'char *' but the argument has type 'int'}} } void check_char(unsigned char x, signed char y) { printf("%c", y); // no-warning printf("%hhu", x); // no-warning printf("%hhi", y); // no-warning printf("%hhi", x); // no-warning printf("%c", x); // no-warning printf("%hhu", y); // no-warning } // Test suppression of individual warnings. void test_suppress_invalid_specifier() { #pragma clang diagnostic push #pragma clang diagnostic ignored "-Wformat-invalid-specifier" printf("%@", 12); // no-warning #pragma clang diagnostic pop } // Make sure warnings are on for next test. #pragma GCC diagnostic warning "-Wformat" #pragma GCC diagnostic warning "-Wformat-security" // Test that the printf call site is where the warning is attached. If the // format string is somewhere else, point to it in a note. void pr9751() { const char kFormat1[] = "%d %d \n"; // expected-note{{format string is defined here}}} printf(kFormat1, 0); // expected-warning{{more '%' conversions than data arguments}} printf("%d %s\n", 0); // expected-warning{{more '%' conversions than data arguments}} const char kFormat2[] = "%18$s\n"; // expected-note{{format string is defined here}} printf(kFormat2, 1, "foo"); // expected-warning{{data argument position '18' exceeds the number of data arguments (2)}} printf("%18$s\n", 1, "foo"); // expected-warning{{data argument position '18' exceeds the number of data arguments (2)}} const char kFormat4[] = "%y"; // expected-note{{format string is defined here}} printf(kFormat4, 5); // expected-warning{{invalid conversion specifier 'y'}} printf("%y", 5); // expected-warning{{invalid conversion specifier 'y'}} const char kFormat5[] = "%."; // expected-note{{format string is defined here}} printf(kFormat5, 5); // expected-warning{{incomplete format specifier}} printf("%.", 5); // expected-warning{{incomplete format specifier}} const char kFormat6[] = "%s"; // expected-note{{format string is defined here}} printf(kFormat6, 5); // expected-warning{{format specifies type 'char *' but the argument has type 'int'}} printf("%s", 5); // expected-warning{{format specifies type 'char *' but the argument has type 'int'}} const char kFormat7[] = "%0$"; // expected-note{{format string is defined here}} printf(kFormat7, 5); // expected-warning{{position arguments in format strings start counting at 1 (not 0)}} printf("%0$", 5); // expected-warning{{position arguments in format strings start counting at 1 (not 0)}} const char kFormat8[] = "%1$d %d"; // expected-note{{format string is defined here}} printf(kFormat8, 4, 4); // expected-warning{{cannot mix positional and non-positional arguments in format string}} printf("%1$d %d", 4, 4); // expected-warning{{cannot mix positional and non-positional arguments in format string}} const char kFormat9[] = ""; // expected-note{{format string is defined here}} printf(kFormat9, 4, 4); // expected-warning{{format string is empty}} printf("", 4, 4); // expected-warning{{format string is empty}} const char kFormat10[] = "\0%d"; // expected-note{{format string is defined here}} printf(kFormat10, 4); // expected-warning{{format string contains '\0' within the string body}} printf("\0%d", 4); // expected-warning{{format string contains '\0' within the string body}} const char kFormat11[] = "%*d"; // expected-note{{format string is defined here}} printf(kFormat11); // expected-warning{{'*' specified field width is missing a matching 'int' argument}} printf("%*d"); // expected-warning{{'*' specified field width is missing a matching 'int' argument}} const char kFormat12[] = "%*d"; // expected-note{{format string is defined here}} printf(kFormat12, 4.4); // expected-warning{{field width should have type 'int', but argument has type 'double'}} printf("%*d", 4.4); // expected-warning{{field width should have type 'int', but argument has type 'double'}} const char kFormat13[] = "%.3p"; // expected-note{{format string is defined here}} void *p; printf(kFormat13, p); // expected-warning{{precision used with 'p' conversion specifier, resulting in undefined behavior}} printf("%.3p", p); // expected-warning{{precision used with 'p' conversion specifier, resulting in undefined behavior}} const char kFormat14[] = "%0s"; // expected-note{{format string is defined here}} printf(kFormat14, "a"); // expected-warning{{flag '0' results in undefined behavior with 's' conversion specifier}} printf("%0s", "a"); // expected-warning{{flag '0' results in undefined behavior with 's' conversion specifier}} const char kFormat15[] = "%hhs"; // expected-note{{format string is defined here}} printf(kFormat15, "a"); // expected-warning{{length modifier 'hh' results in undefined behavior or no effect with 's' conversion specifier}} printf("%hhs", "a"); // expected-warning{{length modifier 'hh' results in undefined behavior or no effect with 's' conversion specifier}} const char kFormat16[] = "%-0d"; // expected-note{{format string is defined here}} printf(kFormat16, 5); // expected-warning{{flag '0' is ignored when flag '-' is present}} printf("%-0d", 5); // expected-warning{{flag '0' is ignored when flag '-' is present}} // Make sure that the "format string is defined here" note is not emitted // when the original string is within the argument expression. printf(1 ? "yes %d" : "no %d"); // expected-warning 2{{more '%' conversions than data arguments}} const char kFormat17[] = "%hu"; // expected-note{{format string is defined here}}} printf(kFormat17, (int[]){0}); // expected-warning{{format specifies type 'unsigned short' but the argument}} printf("%a", (long double)0); // expected-warning{{format specifies type 'double' but the argument has type 'long double'}} // Test braced char[] initializers. const char kFormat18[] = { "%lld" }; // expected-note{{format string is defined here}} printf(kFormat18, 0); // expected-warning{{format specifies type}} // Make sure we point at the offending argument rather than the format string. const char kFormat19[] = "%d"; // expected-note{{format string is defined here}} printf(kFormat19, 0.0); // expected-warning{{format specifies}} } void __attribute__((format(strfmon,1,2))) monformat(const char *fmt, ...); void __attribute__((format(strftime,1,0))) dateformat(const char *fmt); // Other formats void test_other_formats() { char *str = ""; monformat("", 1); // expected-warning{{format string is empty}} monformat(str); // expected-warning{{format string is not a string literal (potentially insecure)}} dateformat(""); // expected-warning{{format string is empty}} dateformat(str); // no-warning (using strftime non literal is not unsafe) } // Do not warn about unused arguments coming from system headers. // <rdar://problem/11317765> #include <format-unused-system-args.h> void test_unused_system_args(int x) { PRINT1("%d\n", x); // no-warning{{extra argument is system header is OK}} } void pr12761(char c) { // This should not warn even with -fno-signed-char. printf("%hhx", c); } // Test that we correctly merge the format in both orders. extern void test14_foo(const char *, const char *, ...) __attribute__((__format__(__printf__, 1, 3))); extern void test14_foo(const char *, const char *, ...) __attribute__((__format__(__scanf__, 2, 3))); extern void test14_bar(const char *, const char *, ...) __attribute__((__format__(__scanf__, 2, 3))); extern void test14_bar(const char *, const char *, ...) __attribute__((__format__(__printf__, 1, 3))); void test14_zed(int *p) { test14_foo("%", "%d", p); // expected-warning{{incomplete format specifier}} test14_bar("%", "%d", p); // expected-warning{{incomplete format specifier}} } void test_qualifiers(volatile int *vip, const int *cip, const volatile int *cvip) { printf("%n", cip); // expected-warning{{format specifies type 'int *' but the argument has type 'const int *'}} printf("%n", cvip); // expected-warning{{format specifies type 'int *' but the argument has type 'const volatile int *'}} printf("%n", vip); // No warning. printf("%p", cip); // No warning. printf("%p", cvip); // No warning. typedef int* ip_t; typedef const int* cip_t; printf("%n", (ip_t)0); // No warning. printf("%n", (cip_t)0); // expected-warning{{format specifies type 'int *' but the argument has type 'cip_t' (aka 'const int *')}} }