Driver: Unbreak ArgList::hasFlag.

- <rdar://problem/6726511> [driver] clang does not have -msoft-float
   hooked up.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@68044 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Driver/ArgList.cpp

@@ -51,7 +51,7 @@ Arg *ArgList::getLastArg(options::ID Id0, options::ID Id1, bool Claim) const {
 
 bool ArgList::hasFlag(options::ID Pos, options::ID Neg, bool Default) const {
   Arg *PosA = getLastArg(Pos);
-  Arg *NegA = getLastArg(Pos);
+  Arg *NegA = getLastArg(Neg);
   if (PosA && NegA)
     return NegA->getIndex() < PosA->getIndex();
   if (PosA) return true;

test/Driver/flags.c

@@ -0,0 +1,9 @@
+// RUN: clang -ccc-host-triple i386-apple-darwin9 -### -S -msoft-float %s 2> %t.log &&
+// RUN: grep '"--soft-float"' %t.log &&
+
+// RUN: clang -ccc-host-triple i386-apple-darwin9 -### -S -msoft-float -mno-soft-float %s 2> %t.log &&
+// RUN: grep '"--soft-float"' %t.log | count 0 &&
+
+// RUN: clang -ccc-host-triple i386-apple-darwin9 -### -S -mno-soft-float %s -msoft-float 2> %t.log &&
+// RUN: grep '"--soft-float"' %t.log
+