clang-cl: Add more tests for the interaction of /FI and /Yc /Yu.

Most things even work; see the included FIXMEs for things that need polishing.

Also don't warn about unused flags for the `/Yuh2.h /FIh1.h /FIh2.h`.  The
common case is that the pch was built with `/Ych2.h /FIh1.h /FIh2.h`, so h1.h
is in the PCH, and we shouldn't warn about /FIh1.h not having an effect.
(If we wanted to get fancy, we could store the list of -include flags in the
pch and then check that it matches later on.)

llvm-svn: 264178

1 files changed, 4 insertions, 2 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 9939ce1e315..b18ddd442db 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -428,7 +428,7 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
       // FIXME: The code here assumes that /Yc and /Yu refer to the same file.
       // cl.exe seems to support both flags with different values, but that
       // seems strange (which flag does /Fp now refer to?), so don't implement
-      // that until someone needs that.
+      // that until someone needs it.
       int PchIndex = YcIndex != -1 ? YcIndex : YuIndex;
       if (PchIndex != -1) {
         if (isa<PrecompileJobAction>(JA)) {
@@ -438,8 +438,10 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
             continue;
         } else {
           // When using the pch, skip all includes prior to the pch.
-          if (AI < PchIndex)
+          if (AI < PchIndex) {
+            A->claim();
             continue;
+          }
           if (AI == PchIndex) {
             A->claim();
             CmdArgs.push_back("-include-pch");