Improve driver error message when only running the preprocessor and an input is
already preprocessed.
--
ddunbar@giles:tmp$ touch t.i
ddunbar@giles:tmp$ gcc -E t.i
ddunbar@giles:tmp$ clang -E t.i
clang: warning: t.i: previously preprocessed input unused when '-E' is present
ddunbar@giles:tmp$
--
<rdar://problem/6813375> [driver] driver prints confusing message when running -E on preprocessed file
llvm-svn: 82120
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 6fb7c98..1d72b0d 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -803,10 +803,19 @@
if (InitialPhase > FinalPhase) {
// Claim here to avoid the more general unused warning.
InputArg->claim();
- Diag(clang::diag::warn_drv_input_file_unused)
- << InputArg->getAsString(Args)
- << getPhaseName(InitialPhase)
- << FinalPhaseArg->getOption().getName();
+
+ // Special case '-E' warning on a previously preprocessed file to make
+ // more sense.
+ if (InitialPhase == phases::Compile && FinalPhase == phases::Preprocess &&
+ getPreprocessedType(InputType) == types::TY_INVALID)
+ Diag(clang::diag::warn_drv_preprocessed_input_file_unused)
+ << InputArg->getAsString(Args)
+ << FinalPhaseArg->getOption().getName();
+ else
+ Diag(clang::diag::warn_drv_input_file_unused)
+ << InputArg->getAsString(Args)
+ << getPhaseName(InitialPhase)
+ << FinalPhaseArg->getOption().getName();
continue;
}