Pythod extension Linux tweaks (#1125)

samples/python_extension/README.md

@@ -7,6 +7,11 @@ lands.
 
 To build and run the sample do the following:
 
+*   Install Python with development headers, i.e.
+    ```
+    sudo apt install python-dev
+    ```
+
 *   Run `build.sh`, it will ask for superuser password to install Python extension
 *   On macOS copy Kotlin binary to extension's directory and change install name with
     `install_name_tool` tool, i.e.
@@ -15,6 +20,15 @@ To build and run the sample do the following:
     sudo install_name_tool /Library/Python/2.7/site-packages/kotlin_bridge.so \
           -change libserver.dylib @loader_path/libserver.dylib
     ```
+*   On Linux copy Kotlin binary in some place where libraries could be loaded from, i.e.
+    ```
+    cp libserver.so /usr/local/lib/
+    ldconfig
+    ```
+    or modify dynamic loader search path with
+    ```
+    export LD_LIBRARY_PATH=`pwd`
+    ```
 
 *   run Python code using Kotlin functionality with
     ```

samples/python_extension/src/main/c/kotlin_bridge.c

@@ -23,9 +23,9 @@
 
 // Note, that as we cache this in the global, and Kotlin/Native object references
 // are currently thread local, we make this global a TLS variable.
-__thread static server_kref_demo_Server server = { 0 };
+static __thread server_kref_demo_Server server = { 0 };
 
-static T_(Server) getServer() {
+static T_(Server) getServer(void) {
   if (!server.pinned) {
     server = __ kotlin.demo.Server.Server("the server");
   }