Add help text for -MMD, -MD, -MM, -M, -MF.

Also regroup these flags so that alike flags are next to each other, while
keeping the list still mostly alphabetical.

The help text isn't ideal, but I feel it's less maze-like than
http://gcc.gnu.org/onlinedocs/gcc-4.1.2/gcc/Preprocessor-Options.html (look
at the entry for '-MMD' and count how many other entries you need to look up
until you know what it does).

And it looks like -M / -MM are mostly an historical accident and most people
use -MD or -MMD for deps tracking these days, so make -M / -MM refer to
-MD / -MMD instead of the other way round.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@199067 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index e1930a2e956736338ab716d9ee47934270a2d43d..948b4487ab9fcd4b38b4693a8386aa137223030f 100644 (file)
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -218,20 +218,26 @@ def I_ : Flag<["-"], "I-">, Group<I_Group>;
 def I : JoinedOrSeparate<["-"], "I">, Group<I_Group>, Flags<[CC1Option]>,
     HelpText<"Add directory to include search path">;
 def L : JoinedOrSeparate<["-"], "L">, Flags<[RenderJoined]>;
-def MD : Flag<["-"], "MD">, Group<M_Group>;
-def MF : JoinedOrSeparate<["-"], "MF">, Group<M_Group>;
+def MD : Flag<["-"], "MD">, Group<M_Group>,
+    HelpText<"Write a depfile containing user and system headers">;
+def MMD : Flag<["-"], "MMD">, Group<M_Group>,
+    HelpText<"Write a depfile containing user headers">;
+def M : Flag<["-"], "M">, Group<M_Group>,
+    HelpText<"Like -MD, but also implies -E and writes to stdout by default">;
+def MM : Flag<["-"], "MM">, Group<M_Group>,
+    HelpText<"Like -MMD, but also implies -E and writes to stdout by default">;
+def MF : JoinedOrSeparate<["-"], "MF">, Group<M_Group>,
+    HelpText<"Write depfile output from -MMD, -MD, -MM, or -M to <file>">,
+    MetaVarName<"<file>">;
 def MG : Flag<["-"], "MG">, Group<M_Group>, Flags<[CC1Option]>,
-    HelpText<"Add missing headers to dependency list">;
-def MMD : Flag<["-"], "MMD">, Group<M_Group>;
-def MM : Flag<["-"], "MM">, Group<M_Group>;
+    HelpText<"Add missing headers to depfile">;
 def MP : Flag<["-"], "MP">, Group<M_Group>, Flags<[CC1Option]>,
     HelpText<"Create phony target for each dependency (other than main file)">;
 def MQ : JoinedOrSeparate<["-"], "MQ">, Group<M_Group>, Flags<[CC1Option]>,
-    HelpText<"Specify target to quote for dependency">;
+    HelpText<"Specify name of main file output to quote in depfile">;
 def MT : JoinedOrSeparate<["-"], "MT">, Group<M_Group>, Flags<[CC1Option]>,
-    HelpText<"Specify target for dependency">;
+    HelpText<"Specify name of main file output in depfile">;
 def Mach : Flag<["-"], "Mach">;
-def M : Flag<["-"], "M">, Group<M_Group>;
 def O0 : Flag<["-"], "O0">, Group<O_Group>, Flags<[CC1Option]>;
 def O4 : Flag<["-"], "O4">, Group<O_Group>, Flags<[CC1Option]>;
 def ObjCXX : Flag<["-"], "ObjC++">, Flags<[DriverOption]>,