Make std::map usage more portable in language=>flags/defines maps

Older versions of GCC, the HP compiler, and the SGI MIPSpro compiler do
not like the use of make_pair in this case and the conversions it
requires:

  a value of type "const char *" cannot be used to initialize an entity
  of type "char [1]"

  /usr/include/g++-3/stl_pair.h:68: assignment of read-only location

Instead use a map lookup pattern already used throughout the rest of our
source tree.

Source/cmMakefileTargetGenerator.cxx

@@ -249,11 +249,12 @@ void cmMakefileTargetGenerator::WriteCommonCodeRules()
 }
 
 //----------------------------------------------------------------------------
-std::string cmMakefileTargetGenerator::GetFlags(const std::string &l) {
-  std::pair<std::map<std::string, std::string>::iterator, bool>
-    insert_result = this->FlagsByLanguage.insert(std::make_pair(l, ""));
-  if (insert_result.second) {
-    std::string& flags = insert_result.first->second;
+std::string cmMakefileTargetGenerator::GetFlags(const std::string &l)
+{
+  ByLanguageMap::iterator i = this->FlagsByLanguage.find(l);
+  if (i == this->FlagsByLanguage.end())
+    {
+    std::string flags;
     const char *lang = l.c_str();
 
     bool shared = ((this->Target->GetType() == cmTarget::SHARED_LIBRARY) ||
@@ -284,15 +285,19 @@ std::string cmMakefileTargetGenerator::GetFlags(const std::string &l) {
     // Add include directory flags.
     this->LocalGenerator->
       AppendFlags(flags,this->GetFrameworkFlags().c_str());
-  }
-  return insert_result.first->second;
+
+    ByLanguageMap::value_type entry(l, flags);
+    i = this->FlagsByLanguage.insert(entry).first;
+    }
+  return i->second;
 }
 
-std::string cmMakefileTargetGenerator::GetDefines(const std::string &l) {
-  std::pair<std::map<std::string, std::string>::iterator, bool>
-    insert_result = this->DefinesByLanguage.insert(std::make_pair(l, ""));
-  if (insert_result.second) {
-    std::string &defines = insert_result.first->second;
+std::string cmMakefileTargetGenerator::GetDefines(const std::string &l)
+{
+  ByLanguageMap::iterator i = this->DefinesByLanguage.find(l);
+  if (i == this->DefinesByLanguage.end())
+    {
+    std::string defines;
     const char *lang = l.c_str();
     // Add the export symbol definition for shared library objects.
     if(const char* exportMacro = this->Target->GetExportMacro())
@@ -312,8 +317,11 @@ std::string cmMakefileTargetGenerator::GetDefines(const std::string &l) {
       (defines, this->Makefile->GetProperty(defPropName.c_str()), lang);
     this->LocalGenerator->AppendDefines
       (defines, this->Target->GetProperty(defPropName.c_str()), lang);
-  }
-  return insert_result.first->second;
+
+    ByLanguageMap::value_type entry(l, defines);
+    i = this->DefinesByLanguage.insert(entry).first;
+    }
+  return i->second;
 }
 
 void cmMakefileTargetGenerator::WriteTargetLanguageFlags()

Source/cmMakefileTargetGenerator.h

@@ -216,10 +216,11 @@ protected:
   std::string MacContentDirectory;
   std::set<cmStdString> MacContentFolders;
 
+  typedef std::map<cmStdString, cmStdString> ByLanguageMap;
   std::string GetFlags(const std::string &l);
-  std::map<std::string, std::string> FlagsByLanguage;
+  ByLanguageMap FlagsByLanguage;
   std::string GetDefines(const std::string &l);
-  std::map<std::string, std::string> DefinesByLanguage;
+  ByLanguageMap DefinesByLanguage;
 
   // Target-wide Fortran module output directory.
   bool FortranModuleDirectoryComputed;