compiler: make compiler an ordinary vlib/compiler module

* Move compiler/ under vlib/compiler/ .

* Add a minimal compiler/main.v driver program.

* Cleanup compiler/main.v .

* Make most compiler tests pass again.

* Apply the fix by @joe-conigliaro , so that the rest of the compiler tests are fixed too.

* Thanks to @avitkauskas, now the vlib/vcompiler/tests/str_gen_test.v test does not need to be special cased anymore.

* Reapply @joe-conigliaro fix for vgen.

vlib/compiler/cheaders.v

@@ -0,0 +1,172 @@
+module compiler
+
+const (
+
+CommonCHeaders = '
+
+#include <stdio.h>  // TODO remove all these includes, define all function signatures and types manually
+#include <stdlib.h>
+#include <signal.h>
+#include <stdarg.h> // for va_list
+#include <inttypes.h>  // int64_t etc
+#include <string.h> // memcpy
+
+#ifndef _WIN32
+#include <ctype.h>
+#include <locale.h> // tolower
+#include <sys/time.h>
+#include <unistd.h> // sleep	
+#endif
+
+
+#ifdef __APPLE__
+#include <libproc.h> // proc_pidpath
+#include <execinfo.h> // backtrace and backtrace_symbols_fd
+#endif
+
+#ifdef __linux__
+#ifndef __BIONIC__
+#include <execinfo.h> // backtrace and backtrace_symbols_fd
+#endif
+#pragma weak backtrace
+#pragma weak backtrace_symbols_fd
+#endif
+
+
+#ifdef __linux__
+#include <sys/types.h>
+#include <sys/wait.h> // os__wait uses wait on nix
+#endif
+
+#ifdef __FreeBSD__
+#include <sys/types.h>
+#include <sys/wait.h> // os__wait uses wait on nix
+#endif
+
+#ifdef __DragonFly__
+#include <sys/types.h>
+#include <sys/wait.h> // os__wait uses wait on nix
+#endif
+
+#define EMPTY_STRUCT_DECLARATION
+#define EMPTY_STRUCT_INITIALIZATION 0
+// Due to a tcc bug, the length of an array needs to be specified, but GCC crashes if it is...
+#define EMPTY_ARRAY_OF_ELEMS(x,n) (x[])
+#define TCCSKIP(x) x
+
+#ifdef __TINYC__
+#undef EMPTY_STRUCT_INITIALIZATION
+#define EMPTY_STRUCT_INITIALIZATION
+#undef EMPTY_ARRAY_OF_ELEMS
+#define EMPTY_ARRAY_OF_ELEMS(x,n) (x[n])
+#undef TCCSKIP
+#define TCCSKIP(x)
+#endif
+
+#define OPTION_CAST(x) (x)
+
+#ifdef _WIN32
+#define WINVER 0x0600
+#define _WIN32_WINNT 0x0600
+#define WIN32_LEAN_AND_MEAN
+#define _UNICODE
+#define UNICODE
+#include <windows.h>
+
+// must be included after <windows.h>
+#ifndef __TINYC__
+#include <shellapi.h>
+#endif
+
+#include <io.h> // _waccess
+#include <fcntl.h> // _O_U8TEXT
+#include <direct.h> // _wgetcwd
+//#include <WinSock2.h>
+#ifdef _MSC_VER
+// On MSVC these are the same (as long as /volatile:ms is passed)
+#define _Atomic volatile
+
+// MSVC cannot parse some things properly
+#undef EMPTY_STRUCT_DECLARATION
+#undef OPTION_CAST
+
+#define EMPTY_STRUCT_DECLARATION int ____dummy_variable
+#define OPTION_CAST(x)
+#endif
+
+#else
+#include <pthread.h>
+#endif
+
+//================================== TYPEDEFS ================================*/
+
+typedef int64_t i64;
+typedef int16_t i16;
+typedef int8_t i8;
+typedef uint64_t u64;
+typedef uint32_t u32;
+typedef uint16_t u16;
+typedef uint8_t byte;
+typedef uint32_t rune;
+typedef float f32;
+typedef double f64;
+typedef unsigned char* byteptr;
+typedef int* intptr;
+typedef void* voidptr;
+typedef struct array array;
+typedef struct map map;
+typedef array array_string;
+typedef array array_int;
+typedef array array_byte;
+typedef array array_f32;
+typedef array array_f64;
+typedef map map_int;
+typedef map map_string;
+#ifndef bool
+	typedef int bool;
+	#define true 1
+	#define false 0
+#endif
+
+//============================== HELPER C MACROS =============================*/
+#define _PUSH(arr, val, tmp, tmp_typ) {tmp_typ tmp = (val); array_push(arr, &tmp);}
+#define _PUSH_MANY(arr, val, tmp, tmp_typ) {tmp_typ tmp = (val); array_push_many(arr, tmp.data, tmp.len);}
+#define _IN(typ, val, arr) array_##typ##_contains(arr, val)
+#define _IN_MAP(val, m) map_exists(m, val)
+#define DEFAULT_EQUAL(a, b) (a == b)
+#define DEFAULT_NOT_EQUAL(a, b) (a != b)
+#define DEFAULT_LT(a, b) (a < b)
+#define DEFAULT_LE(a, b) (a <= b)
+#define DEFAULT_GT(a, b) (a > b)
+#define DEFAULT_GE(a, b) (a >= b)
+//================================== GLOBALS =================================*/
+byteptr g_str_buf;
+int load_so(byteptr);
+void reload_so();
+'
+
+js_headers = '
+
+var array_string = function() {}
+var array_byte = function() {}
+var array_int = function() {}
+var byte = function() {}
+var double = function() {}
+var int = function() {}
+var f64 = function() {}
+var f32 = function() {}
+var i64 = function() {}
+var i32 = function() {}
+var i16 = function() {}
+var u64 = function() {}
+var u32 = function() {}
+var u16 = function() {}
+var i8 = function() {}
+var u8 = function() {}
+var bool = function() {}
+var rune = function() {}
+var map_string = function() {}
+var map_int = function() {}
+
+'
+)