commit 0db667aadbc4d6f698be4dce56b6473e2fc49aac
author Chris Lattner <sabre@nondot.org> Sat Oct 06 06:57:34 2007 +0000
committer Chris Lattner <sabre@nondot.org> Sat Oct 06 06:57:34 2007 +0000
tree ed6fe1534e59ae46e3ab178c5a3333e125a691e9
parent 8c9d29f7aaf238a7b94ae517929a03a74adc6dcf

speed up clang startup another 28% by avoiding std::vector<std::string> 
for holding builtin target-specific macros.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@42689 91177308-0d34-0410-b5e6-96231b3b80d8

Driver/clang.cpp

diff --git a/Driver/clang.cpp b/Driver/clang.cpp
index b5c1559..f1dc6a0 100644
--- a/Driver/clang.cpp
+++ b/Driver/clang.cpp
@@ -744,6 +744,8 @@
                                        HeaderSearch &HeaderInfo,
                                        const LangOptions &LangInfo,
                                        std::vector<char> &PrologMacros) {
+  PrologMacros.reserve(4080);
+  
   FileManager &FileMgr = HeaderInfo.getFileMgr();
   
   // Install things like __POWERPC__, __GNUC__, etc into the macro table.