Allow VersionPrinter to print to arbitrary raw_ostreams

Summary:
I would like to add printing of registered targets to clang's version
information.  For this to work correctly, the VersionPrinter logic in
CommandLine.cpp should support printing to arbitrary raw_ostreams,
instead of always defaulting to outs().

Add a raw_ostream& parameter to the function pointer type used for
VersionPrinter, and while doing so, introduce a typedef for convenience.

Note that VersionPrinter::print() will still default to using outs(),
the clang part will necessarily go into a separate review.

Reviewers: beanz, chandlerc, dberris, mehdi_amini, zturner

Reviewed By: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33899

llvm-svn: 304835

1 files changed, 8 insertions, 10 deletions

diff --git a/llvm/lib/Support/CommandLine.cpp b/llvm/lib/Support/CommandLine.cpp
index 34345901eab..de0ca940b40 100644
--- a/llvm/lib/Support/CommandLine.cpp
+++ b/llvm/lib/Support/CommandLine.cpp
@@ -2042,9 +2042,9 @@ void CommandLineParser::printOptionValues() {
     Opts[i].second->printOptionValue(MaxArgLen, PrintAllOptions);
 }
 
-static void (*OverrideVersionPrinter)() = nullptr;
+static VersionPrinterTy OverrideVersionPrinter = nullptr;
 
-static std::vector<void (*)()> *ExtraVersionPrinters = nullptr;
+static std::vector<VersionPrinterTy> *ExtraVersionPrinters = nullptr;
 
 namespace {
 class VersionPrinter {
@@ -2084,7 +2084,7 @@ public:
       return;
 
     if (OverrideVersionPrinter != nullptr) {
-      (*OverrideVersionPrinter)();
+      OverrideVersionPrinter(outs());
       exit(0);
     }
     print();
@@ -2093,10 +2093,8 @@ public:
     // information.
     if (ExtraVersionPrinters != nullptr) {
       outs() << '\n';
-      for (std::vector<void (*)()>::iterator I = ExtraVersionPrinters->begin(),
-                                             E = ExtraVersionPrinters->end();
-           I != E; ++I)
-        (*I)();
+      for (auto I : *ExtraVersionPrinters)
+        I(outs());
     }
 
     exit(0);
@@ -2134,11 +2132,11 @@ void cl::PrintHelpMessage(bool Hidden, bool Categorized) {
 /// Utility function for printing version number.
 void cl::PrintVersionMessage() { VersionPrinterInstance.print(); }
 
-void cl::SetVersionPrinter(void (*func)()) { OverrideVersionPrinter = func; }
+void cl::SetVersionPrinter(VersionPrinterTy func) { OverrideVersionPrinter = func; }
 
-void cl::AddExtraVersionPrinter(void (*func)()) {
+void cl::AddExtraVersionPrinter(VersionPrinterTy func) {
   if (!ExtraVersionPrinters)
-    ExtraVersionPrinters = new std::vector<void (*)()>;
+    ExtraVersionPrinters = new std::vector<VersionPrinterTy>;
 
   ExtraVersionPrinters->push_back(func);
 }