fix the second half of PR4006 and rdar://6807000 by treating
() as being either zero arguments or one empty argument depending
on situation.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@69627 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index 330e2a1..48c166d 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -392,7 +392,16 @@
if (NumActuals < MinArgsExpected) {
// There are several cases where too few arguments is ok, handle them now.
- if (NumActuals+1 == MinArgsExpected && MI->isVariadic()) {
+ if (NumActuals == 0 && MinArgsExpected == 1) {
+ // #define A(X) or #define A(...) ---> A()
+
+ // If there is exactly one argument, and that argument is missing,
+ // then we have an empty "()" argument empty list. This is fine, even if
+ // the macro expects one argument (the argument is just empty).
+ isVarargsElided = MI->isVariadic();
+ } else if (MI->isVariadic() &&
+ (NumActuals+1 == MinArgsExpected || // A(x, ...) -> A(X)
+ (NumActuals == 0 && MinArgsExpected == 2))) {// A(x,...) -> A()
// Varargs where the named vararg parameter is missing: ok as extension.
// #define A(x, ...)
// A("blah")
@@ -404,12 +413,7 @@
// #define B(x, ...) blah(a, ## __VA_ARGS__)
// #define C(...) blah(a, ## __VA_ARGS__)
// A(x) B(x) C()
- isVarargsElided = true; //MI->getNumArgs() > 1;
- } else if (NumActuals == 0 && MinArgsExpected == 1) {
- assert(!MI->isVariadic() && "Variadic should be handled by case above");
- // If there is exactly one argument, and that argument is missing,
- // then we have an empty "()" argument empty list. This is fine, even if
- // the macro expects one argument (the argument is just empty).
+ isVarargsElided = true;
} else {
// Otherwise, emit the error.
Diag(Tok, diag::err_too_few_args_in_macro_invoc);
diff --git a/test/Preprocessor/macro_fn.c b/test/Preprocessor/macro_fn.c
index 90dc2f0..98ebaee 100644
--- a/test/Preprocessor/macro_fn.c
+++ b/test/Preprocessor/macro_fn.c
@@ -4,6 +4,8 @@
#define zero() 0
#define one(x) 0
#define two(x, y) 0
+#define zero_dot(...) 0 /* expected-warning {{variadic macros were introduced in C99}} */
+#define one_dot(x, ...) 0 /* expected-warning {{variadic macros were introduced in C99}} */
zero()
zero(1); /* expected-error {{too many arguments provided to function-like macro invocation}} */
@@ -28,6 +30,11 @@
-/* PR4006 */
+/* PR4006 & rdar://6807000 */
#define e(...) __VA_ARGS__ /* expected-warning {{variadic macros were introduced in C99}} */
e(x)
+e()
+
+zero_dot()
+one_dot(x) /* empty ... argument: expected-warning {{varargs argument missing, but tolerated as an extension}} */
+one_dot() /* empty first argument, elided ...: expected-warning {{varargs argument missing, but tolerated as an extension}} */