Update Omake for Linux running

src/omake/MakeMain.cpp

@@ -306,11 +306,18 @@ bool MakeMain::LoadJobArgs()
 }
 void MakeMain::LoadEnvironment()
 {
-#ifdef TARGET_OS_WINDOWS
-    char** env = environ;
-#else
-    char** env = 0;
+// https://www.man7.org/linux/man-pages/man7/environ.7.html
+/*
+ *Historically and by standard, environ must be declared in the
+ *user program.  However, as a (nonstandard) programmer
+ *convenience, environ is declared in the header file <unistd.h> if
+ *the _GNU_SOURCE feature test macro is defined (see
+ *feature_test_macros(7)).
+ */
+#ifndef TARGET_OS_WINDOWS
+    extern char** environ;
 #endif
+    char** env = environ;
     Variable::Origin origin;
     if (environOverride.GetValue())
         origin = Variable::o_environ_override;

src/omake/Maker.cpp

@@ -60,7 +60,7 @@ Maker::Maker(bool Silent, bool DisplayOnly, bool IgnoreResults, bool Touch, Outp
     Variable* v = VariableContainer::Instance()->Lookup("SHELL");
     std::string shtest = v->GetValue();
     std::transform(shtest.begin(), shtest.end(), shtest.begin(), ::toupper);
-    OS::SetSHEXE(shtest.find("SH.EXE") != std::string::npos || shtest.find("BASH.EXE") != std::string::npos);
+    OS::SetSHEXE(shtest.find("sh") != std::string::npos);
 }
 Maker::~Maker() {}
 void Maker::SetFirstGoal(const std::string& name)

src/omake/Variable.cpp

@@ -1,26 +1,26 @@
 /* Software License Agreement
- * 
+ *
  *     Copyright(C) 1994-2024 David Lindauer, (LADSoft)
- * 
+ *
  *     This file is part of the Orange C Compiler package.
- * 
+ *
  *     The Orange C Compiler package is free software: you can redistribute it and/or modify
  *     it under the terms of the GNU General Public License as published by
  *     the Free Software Foundation, either version 3 of the License, or
  *     (at your option) any later version.
- * 
+ *
  *     The Orange C Compiler package is distributed in the hope that it will be useful,
  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *     GNU General Public License for more details.
- * 
+ *
  *     You should have received a copy of the GNU General Public License
  *     along with Orange C.  If not, see <http://www.gnu.org/licenses/>.
- * 
+ *
  *     contact information:
  *         email: [email protected] <David Lindauer>
- * 
- * 
+ *
+ *
  */
 
 #include "Variable.h"
@@ -85,6 +85,8 @@ Variable* VariableContainer::Lookup(const std::string& name)
 }
 void VariableContainer::operator+(Variable* variable)
 {
+    if (!variable)
+        return;
     std::unique_ptr<Variable> temp(variable);
     if (variable->GetName().find_first_of('%') != std::string::npos)
     {