Support the 'a' scanf length modifier as an extension in C++.

It should not be supported in C++11, since that uses the C99 standard
library, in which 'a' is a format specifier.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147310 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/FormatString.cpp b/lib/Analysis/FormatString.cpp
index bbc6f07b36dfa5bab52e9c50c168899cdeceeda4..8e295aa2be1c333d9e49078a334b96949c0d6083 100644 (file)
--- a/lib/Analysis/FormatString.cpp
+++ b/lib/Analysis/FormatString.cpp
@@ -200,7 +200,7 @@ clang::analyze_format_string::ParseLengthModifier(FormatSpecifier &FS,
     case 'L': lmKind = LengthModifier::AsLongDouble; ++I; break;
     case 'q': lmKind = LengthModifier::AsLongLong;   ++I; break;
     case 'a':
-      if (IsScanf && !LO.C99 && !LO.CPlusPlus) {
+      if (IsScanf && !LO.C99 && !LO.CPlusPlus0x) {
         // For scanf in C90, look at the next character to see if this should
         // be parsed as the GNU extension 'a' length modifier. If not, this
         // will be parsed as a conversion specifier.

diff --git a/test/SemaCXX/format-strings-0x.cpp b/test/SemaCXX/format-strings-0x.cpp
new file mode 100644 (file)
index 0000000..61bdbe1
--- /dev/null
+++ b/test/SemaCXX/format-strings-0x.cpp
@@ -0,0 +1,13 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -pedantic -std=c++11 %s
+
+extern "C" {
+extern int scanf(const char *restrict, ...);
+extern int printf(const char *restrict, ...);
+}
+
+void f(char **sp, float *fp) {
+  scanf("%as", sp); // expected-warning{{conversion specifies type 'float *' but the argument has type 'char **'}}
+
+  printf("%a", 1.0);
+  scanf("%afoobar", fp);
+}

diff --git a/test/SemaCXX/format-strings.cpp b/test/SemaCXX/format-strings.cpp
new file mode 100644 (file)
index 0000000..2011a71
--- /dev/null
+++ b/test/SemaCXX/format-strings.cpp
@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -pedantic %s
+
+extern "C" {
+extern int scanf(const char *restrict, ...);
+extern int printf(const char *restrict, ...);
+}
+
+void f(char **sp, float *fp) {
+  // TODO: Warn that the 'a' length modifier is an extension.
+  scanf("%as", sp);
+
+  // TODO: Warn that the 'a' conversion specifier is a C++11 feature.
+  printf("%a", 1.0);
+  scanf("%afoobar", fp);
+}