Added FixIt support to printf format string checking.

- Refactored LengthModifier to be a class.
- Added toString methods in all member classes of FormatSpecifier.
- FixIt suggestions keep user specified flags unless incorrect.

Limitations:
- The suggestions are not conversion specifier sensitive. For example, if we have a 'pad with zeroes' flag, and the correction is a string conversion specifier, we do not remove the flag. Clang will warn us on the next compilation.

A    test/Sema/format-strings-fixit.c
M    include/clang/Analysis/Analyses/PrintfFormatString.h
M    lib/Analysis/PrintfFormatString.cpp
M    lib/Sema/SemaChecking.cpp


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@105680 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 20 insertions, 0 deletions

diff --git a/test/Sema/format-strings-fixit.c b/test/Sema/format-strings-fixit.c
new file mode 100644
index 0000000000..ba38973049
--- /dev/null
+++ b/test/Sema/format-strings-fixit.c
@@ -0,0 +1,20 @@
+// RUN: cp %s %t
+// RUN: %clang_cc1 -pedantic -Wall -fixit %t || true
+// RUN: %clang_cc1 -fsyntax-only -pedantic -Wall -Werror %t
+
+/* This is a test of the various code modification hints that are
+   provided as part of warning or extension diagnostics. All of the
+   warnings will be fixed by -fixit, and the resulting file should
+   compile cleanly with -Werror -pedantic. */
+
+int printf(char const *, ...);
+
+void test() {
+  printf("%0s", (int) 123);
+  printf("abc%f", "testing testing 123");
+  printf("%u", (long) -12);
+  printf("%+.2d", (unsigned long long) 123456);
+  printf("%1d", (long double) 1.23);
+  printf("%Ld", (long double) -4.56);
+  printf("%1$f:%2$.*3$f:%4$.*3$f\n", 1, 2, 3, 4);
+}