Fix two bugs in format-string checking:
(1) Do not assume the data arguments start after the format string
(2) Do not use the fact that a function is variadic to treat it like a va_list printf function
Fixes PR 6697.
llvm-svn: 99480
diff --git a/clang/test/Sema/format-strings.c b/clang/test/Sema/format-strings.c
index 4db775f..dcc4c35 100644
--- a/clang/test/Sema/format-strings.c
+++ b/clang/test/Sema/format-strings.c
@@ -238,3 +238,16 @@
printf("%2$*8$d", (int) 2, (int) 3); // expected-warning{{specified field width is missing a matching 'int' argument}}
}
+// 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{{conversion 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{{conversion specifies type 'char *' but the argument has type 'int'}}
+}
+