From 2e98c3d0644fc0c265844908f43b7e4526dd819c Mon Sep 17 00:00:00 2001 From: Mike Pall Date: Thu, 23 Jun 2022 09:10:09 +0200 Subject: Grammar and spell check. --- doc/ext_c_api.html | 4 ++-- doc/ext_ffi.html | 14 +++++------ doc/ext_ffi_api.html | 10 ++++---- doc/ext_ffi_semantics.html | 58 +++++++++++++++++++++++----------------------- doc/ext_ffi_tutorial.html | 24 +++++++++---------- doc/ext_jit.html | 4 ++-- doc/extensions.html | 8 +++---- doc/faq.html | 6 ++--- doc/install.html | 8 +++---- doc/running.html | 4 ++-- doc/status.html | 4 ++-- 11 files changed, 72 insertions(+), 72 deletions(-) (limited to 'doc') diff --git a/doc/ext_c_api.html b/doc/ext_c_api.html index a5d02473..b328047a 100644 --- a/doc/ext_c_api.html +++ b/doc/ext_c_api.html @@ -103,7 +103,7 @@ Turn the whole JIT compiler on or off or flush the whole cache of compiled code. This sets the mode for the function at the stack index idx or the parent of the calling function (idx = 0). It either enables JIT compilation for a function, disables it and flushes any -already compiled code or only flushes already compiled code. This +already compiled code, or only flushes already compiled code. This applies recursively to all sub-functions of the function with LUAJIT_MODE_ALLFUNC or only to the sub-functions with LUAJIT_MODE_ALLSUBFUNC. @@ -122,7 +122,7 @@ traces which link to it. This mode defines a wrapper function for calls to C functions. If called with LUAJIT_MODE_ON, the stack index at idx must be a lightuserdata object holding a pointer to the wrapper -function. From now on all C functions are called through the wrapper +function. From now on, all C functions are called through the wrapper function. If called with LUAJIT_MODE_OFF this mode is turned off and all C functions are directly called.

diff --git a/doc/ext_ffi.html b/doc/ext_ffi.html index 7a87ca65..04b78d98 100644 --- a/doc/ext_ffi.html +++ b/doc/ext_ffi.html @@ -153,7 +153,7 @@ call the binding function. Phew!

Motivating Example: Using C Data Structures

The FFI library allows you to create and access C data -structures. Of course the main use for this is for interfacing with +structures. Of course, the main use for this is for interfacing with C functions. But they can be used stand-alone, too.

@@ -165,7 +165,7 @@ implemented with a big table holding lots of tiny tables. This imposes both a substantial memory overhead as well as a performance overhead.

-Here's a sketch of a library that operates on color images plus a +Here's a sketch of a library that operates on color images, plus a simple benchmark. First, the plain Lua version: 

@@ -180,7 +180,7 @@ local function image_ramp_green(n)
   return img
 end
 
-local function image_to_grey(img, n)
+local function image_to_gray(img, n)
   for i=1,n do
     local y = floor(0.3*img[i].red + 0.59*img[i].green + 0.11*img[i].blue)
     img[i].red = y; img[i].green = y; img[i].blue = y
@@ -190,14 +190,14 @@ end
 local N = 400*400
 local img = image_ramp_green(N)
 for i=1,1000 do
-  image_to_grey(img, N)
+  image_to_gray(img, N)
 end

This creates a table with 160.000 pixels, each of which is a table -holding four number values in the range of 0-255. First an image with +holding four number values in the range of 0-255. First, an image with a green ramp is created (1D for simplicity), then the image is -converted to greyscale 1000 times. Yes, that's silly, but I was in +converted to grayscale 1000 times. Yes, that's silly, but I was in need of a simple example ...

@@ -304,7 +304,7 @@ be more compact and faster. This is certainly true (by a factor of ~1.7x). Switching to a struct-of-arrays would help, too.

-However the resulting code would be less idiomatic and rather +However, the resulting code would be less idiomatic and rather error-prone. And it still doesn't get even close to the performance of the FFI version of the code. Also, high-level data structures cannot be easily passed to other C functions, especially I/O functions, diff --git a/doc/ext_ffi_api.html b/doc/ext_ffi_api.html index 687b85c5..962db6dc 100644 --- a/doc/ext_ffi_api.html +++ b/doc/ext_ffi_api.html @@ -117,7 +117,7 @@ separated by semicolons. The trailing semicolon for a single declaration may be omitted.

-Please note that external symbols are only declared, but they +Please note, that external symbols are only declared, but they are not bound to any specific address, yet. Binding is achieved with C library namespaces (see below).

@@ -205,7 +205,7 @@ parse the cdecl only once and get its ctype with ffi.typeof(). Then use the ctype as a constructor repeatedly.

-Please note that an anonymous struct declaration implicitly +Please note, that an anonymous struct declaration implicitly creates a new and distinguished ctype every time you use it for ffi.new(). This is probably not what you want, especially if you create more than one cdata object. Different anonymous @@ -252,12 +252,12 @@ afterwards. Neither the contents of the metatable nor the contents of an __index table (if any) may be modified afterwards. The associated metatable automatically applies to all uses of this type, no matter how the objects are created or where they -originate from. Note that pre-defined operations on types have +originate from. Note that predefined operations on types have precedence (e.g. declared field names cannot be overridden).

All standard Lua metamethods are implemented. These are called directly, -without shortcuts and on any mix of types. For binary operations, the +without shortcuts, and on any mix of types. For binary operations, the left operand is checked first for a valid ctype metamethod. The __gc metamethod only applies to struct/union types and performs an implicit ffi.gc() @@ -484,7 +484,7 @@ have some extra methods:

Free the resources associated with a callback. The associated Lua function is unanchored and may be garbage collected. The callback -function pointer is no longer valid and must not be called anymore +function pointer is no longer valid and must not be called again (it may be reused by a subsequently created callback).

diff --git a/doc/ext_ffi_semantics.html b/doc/ext_ffi_semantics.html index 4909fedd..6c6f8ad7 100644 --- a/doc/ext_ffi_semantics.html +++ b/doc/ext_ffi_semantics.html @@ -84,7 +84,7 @@ footprint. It's used by the ffi.* library functions to declare C types or external symbols.

-It's only purpose is to parse C declarations, as found e.g. in +Its only purpose is to parse C declarations, as found e.g. in C header files. Although it does evaluate constant expressions, it's not a C compiler. The body of inline C function definitions is simply ignored. @@ -161,7 +161,7 @@ function declarations.

-The following C types are pre-defined by the C parser (like +The following C types are predefined by the C parser (like a typedef, except re-declarations will be ignored):

A ctype object can be indexed with a string key, too. The only -pre-defined operation is reading scoped constants of +predefined operation is reading scoped constants of struct/union types. All other accesses defer to the corresponding metamethods or index tables (if any).

@@ -650,7 +650,7 @@ certain optimizations.

As a consequence, the elements of complex numbers and vectors are immutable. But the elements of an aggregate holding these -types may be modified of course. I.e. you cannot assign to +types may be modified, of course. I.e. you cannot assign to foo.c.im, but you can assign a (newly created) complex number to foo.c.

@@ -669,8 +669,8 @@ through unions is explicitly detected and allowed. to ffi.new(ct, ...), unless a __new metamethod is defined. The __new metamethod is called with the ctype object plus any other arguments passed to the constructor. Note that you have to -use ffi.new inside of it, since calling ct(...) would -cause infinite recursion. +use ffi.new inside the metamethod, since calling ct(...) +would cause infinite recursion.
  • C function call: a cdata function or cdata function pointer can be called. The passed arguments are @@ -681,7 +681,7 @@ variable argument part of vararg C function use C function is called and the return value (if any) is converted to a Lua object.
    On Windows/x86 systems, __stdcall functions are automatically -detected and a function declared as __cdecl (the default) is +detected, and a function declared as __cdecl (the default) is silently fixed up after the first call.
    • @@ -691,7 +691,7 @@ silently fixed up after the first call.
  • Pointer arithmetic: a cdata pointer/array and a cdata number or a Lua number can be added or subtracted. The number must be -on the right hand side for a subtraction. The result is a pointer of +on the right-hand side for a subtraction. The result is a pointer of the same type with an address plus or minus the number value multiplied by the element size in bytes. An error is raised if the element size is undefined.
    • @@ -706,7 +706,7 @@ operators (+ - * / % ^ and unary minus) can be applied to two cdata numbers, or a cdata number and a Lua number. If one of them is an uint64_t, the other side is converted to an uint64_t and an unsigned arithmetic operation -is performed. Otherwise both sides are converted to an +is performed. Otherwise, both sides are converted to an int64_t and a signed arithmetic operation is performed. The result is a boxed 64 bit cdata object.
    @@ -737,7 +737,7 @@ which is compatible with any other pointer type.
  • 64 bit integer comparison: two cdata numbers, or a cdata number and a Lua number can be compared with each other. If one of them is an uint64_t, the other side is converted to an -uint64_t and an unsigned comparison is performed. Otherwise +uint64_t and an unsigned comparison is performed. Otherwise, both sides are converted to an int64_t and a signed comparison is performed.
    @@ -762,9 +762,9 @@ keys! A cdata object is treated like any other garbage-collected object and is hashed and compared by its address for table indexing. Since there's no interning for cdata value types, the same value may be -boxed in different cdata objects with different addresses. Thus +boxed in different cdata objects with different addresses. Thus, t[1LL+1LL] and t[2LL] usually do not point to -the same hash slot and they certainly do not point to the same +the same hash slot, and they certainly do not point to the same hash slot as t[2].

    @@ -786,7 +786,7 @@ the resulting Lua number as a key when indexing tables.
    One obvious benefit: t[tonumber(2LL)] does point to the same slot as t[2].

    • -
  • Otherwise use either tostring() on 64 bit integers +
  • Otherwise, use either tostring() on 64 bit integers or complex numbers or combine multiple fields of a cdata aggregate to a Lua string (e.g. with ffi.string()). Then @@ -794,7 +794,7 @@ use the resulting Lua string as a key when indexing tables.
  • Create your own specialized hash table implementation using the C types provided by the FFI library, just like you would in -C code. Ultimately this may give much better performance than the +C code. Ultimately, this may give much better performance than the other alternatives or what a generic by-value hash table could possibly provide.
    • @@ -860,7 +860,7 @@ garbage collector will automatically free the memory used by it (at the end of the next GC cycle).

    -Please note that pointers themselves are cdata objects, however they +Please note, that pointers themselves are cdata objects, however they are not followed by the garbage collector. So e.g. if you assign a cdata array to a pointer, you must keep the cdata object holding the array alive as long as the pointer is still in use: @@ -909,18 +909,18 @@ of the function pointer and the Lua function object (closure).

    This can happen implicitly due to the usual conversions, e.g. when -passing a Lua function to a function pointer argument. Or you can use +passing a Lua function to a function pointer argument. Or, you can use ffi.cast() to explicitly cast a Lua function to a C function pointer.

    -Currently only certain C function types can be used as callback +Currently, only certain C function types can be used as callback functions. Neither C vararg functions nor functions with pass-by-value aggregate argument or result types are supported. There -are no restrictions for the kind of Lua functions that can be called +are no restrictions on the kind of Lua functions that can be called from the callback — no checks for the proper number of arguments are made. The return value of the Lua function will be converted to the -result type and an error will be thrown for invalid conversions. +result type, and an error will be thrown for invalid conversions.

    It's allowed to throw errors across a callback invocation, but it's not @@ -981,7 +981,7 @@ convention cannot be automatically detected, unlike for __stdcall calls to Windows functions.

    -For some use cases it's necessary to free up the resources or to +For some use cases, it's necessary to free up the resources or to dynamically redirect callbacks. Use an explicit cast to a C function pointer and keep the resulting cdata object. Then use the cb:free() @@ -1034,7 +1034,7 @@ GUI application, which waits for user input most of the time, anyway.

    For new designs avoid push-style APIs: a C function repeatedly -calling a callback for each result. Instead use pull-style APIs: +calling a callback for each result. Instead, use pull-style APIs: call a C function repeatedly to get a new result. Calls from Lua to C via the FFI are much faster than the other way round. Most well-designed libraries already use pull-style APIs (read/write, get/put). @@ -1053,7 +1053,7 @@ function.

    Indexing a C library namespace object with a symbol name (a Lua -string) automatically binds it to the library. First the symbol type +string) automatically binds it to the library. First, the symbol type is resolved — it must have been declared with ffi.cdef. Then the symbol address is resolved by searching for the symbol name in the @@ -1108,7 +1108,7 @@ Performance notice: the JIT compiler specializes to the identity of namespace objects and to the strings used to index it. This effectively turns function cdata objects into constants. It's not useful and actually counter-productive to explicitly cache these -function objects, e.g. local strlen = ffi.C.strlen. OTOH it +function objects, e.g. local strlen = ffi.C.strlen. OTOH, it is useful to cache the namespace itself, e.g. local C = ffi.C.

    @@ -1133,14 +1133,14 @@ This behavior is inevitable, since the goal is to provide full interoperability with C code. Adding extra safety measures, like bounds checks, would be futile. There's no way to detect misdeclarations of C functions, since shared libraries only -provide symbol names, but no type information. Likewise there's no way +provide symbol names, but no type information. Likewise, there's no way to infer the valid range of indexes for a returned pointer.

    Again: the FFI library is a low-level library. This implies it needs to be used with care, but it's flexibility and performance often outweigh this concern. If you're a C or C++ developer, it'll be easy -to apply your existing knowledge. OTOH writing code for the FFI +to apply your existing knowledge. OTOH, writing code for the FFI library is not for the faint of heart and probably shouldn't be the first exercise for someone with little experience in Lua, C or C++.

    @@ -1168,7 +1168,7 @@ currently incomplete:
  • C declarations are not passed through a C pre-processor, yet.
  • The C parser is able to evaluate most constant expressions -commonly found in C header files. However it doesn't handle the +commonly found in C header files. However, it doesn't handle the full range of C expression semantics and may fail for some obscure constructs.
  • static const declarations only work for integer types diff --git a/doc/ext_ffi_tutorial.html b/doc/ext_ffi_tutorial.html index c5e423b8..de6b6f5e 100644 --- a/doc/ext_ffi_tutorial.html +++ b/doc/ext_ffi_tutorial.html @@ -81,7 +81,7 @@ of its functions: local ffi = require("ffi")

    -Please note this doesn't define an ffi variable in the table +Please note, this doesn't define an ffi variable in the table of globals — you really need to use the local variable. The require function ensures the library is only loaded once.

    @@ -190,7 +190,7 @@ don't need to declare them as such. ⑤ The poll() function takes a couple more arguments we're not going to use. You can simply use nil to pass a NULL pointer and 0 -for the nfds parameter. Please note that the +for the nfds parameter. Please note, that the number 0 does not convert to a pointer value, unlike in C++. You really have to pass pointers to pointer arguments and numbers to number arguments. @@ -287,12 +287,12 @@ Here's the step-by-step explanation:

    ① This defines some of the C functions provided by zlib. For the sake of this example, some -type indirections have been reduced and it uses the pre-defined +type indirections have been reduced and it uses the predefined fixed-size integer types, while still adhering to the zlib API/ABI.

    ② This loads the zlib shared -library. On POSIX systems it's named libz.so and usually +library. On POSIX systems, it's named libz.so and usually comes pre-installed. Since ffi.load() automatically adds any missing standard prefixes/suffixes, we can simply load the "z" library. On Windows it's named zlib1.dll and @@ -320,7 +320,7 @@ actual length that was used.

    In C you'd pass in the address of a local variable (&buflen). But since there's no address-of operator in -Lua, we'll just pass in a one-element array. Conveniently it can be +Lua, we'll just pass in a one-element array. Conveniently, it can be initialized with the maximum buffer size in one step. Calling the actual zlib.compress2 function is then straightforward.

    @@ -344,7 +344,7 @@ for garbage collection and string interning. ⑥ The uncompress functions does the exact opposite of the compress function. The compressed data doesn't include the size of the original string, -so this needs to be passed in. Otherwise no surprises here. +so this needs to be passed in. Otherwise, no surprises here.

    ⑦ The code, that makes use @@ -378,7 +378,7 @@ Ok, so the ffi.* functions generally accept cdata objects wherever you'd want to use a number. That's why we get a away with passing n to ffi.string() above. But other Lua library functions or modules don't know how to deal with this. So for -maximum portability one needs to use tonumber() on returned +maximum portability, one needs to use tonumber() on returned long results before passing them on. Otherwise the application might work on some systems, but would fail in a POSIX/x64 environment. @@ -450,7 +450,7 @@ the origin.

    ④ If we run out of operators, we can -define named methods, too. Here the __index table defines an +define named methods, too. Here, the __index table defines an area function. For custom indexing needs, one might want to define __index and __newindex functions instead.

    @@ -464,13 +464,13 @@ be used e.g. to create an array of points. The metamethods automatically apply to any and all uses of this type.

    -Please note that the association with a metatable is permanent and +Please note, that the association with a metatable is permanent and the metatable must not be modified afterwards! Ditto for the __index table.

    ⑥ Here are some simple usage examples -for the point type and their expected results. The pre-defined +for the point type and their expected results. The predefined operations (such as a.x) can be freely mixed with the newly defined metamethods. Note that area is a method and must be called with the Lua syntax for methods: a:area(), not @@ -479,7 +479,7 @@ called with the Lua syntax for methods: a:area(), not

    The C type metamethod mechanism is most useful when used in conjunction with C libraries that are written in an object-oriented -style. Creators return a pointer to a new instance and methods take an +style. Creators return a pointer to a new instance, and methods take an instance pointer as the first argument. Sometimes you can just point __index to the library namespace and __gc to the destructor and you're done. But often enough you'll want to add @@ -565,7 +565,7 @@ end

    This turns them into indirect calls and generates bigger and slower -machine code. Instead you'll want to cache the namespace itself and +machine code. Instead, you'll want to cache the namespace itself and rely on the JIT compiler to eliminate the lookups: 

    diff --git a/doc/ext_jit.html b/doc/ext_jit.html
index be1bdcf6..8f58a0c7 100644
--- a/doc/ext_jit.html
+++ b/doc/ext_jit.html
@@ -150,7 +150,7 @@ Contains the target architecture name:
 
 
    jit.opt.* — JIT compiler optimization control
    
 
    
-This sub-module provides the backend for the -O command line
+This submodule provides the backend for the -O command line
 option.
 
    
 
    
@@ -170,7 +170,7 @@ which was one of the ways to enable optimization.
 
 
    jit.util.* — JIT compiler introspection
    
 
    
-This sub-module holds functions to introspect the bytecode, generated
+This submodule holds functions to introspect the bytecode, generated
 traces, the IR and the generated machine code. The functionality
 provided by this module is still in flux and therefore undocumented.
 
    
diff --git a/doc/extensions.html b/doc/extensions.html
index fe4df6f7..3ed13804 100644
--- a/doc/extensions.html
+++ b/doc/extensions.html
@@ -84,7 +84,7 @@ or LuaJIT.
 
    
 
    
 LuaJIT extends the standard Lua VM with new functionality and adds
-several extension modules. Please note this page is only about
+several extension modules. Please note, this page is only about
 functional enhancements and not about performance enhancements,
 such as the optimized VM, the faster interpreter or the JIT compiler.
 
    
@@ -185,7 +185,7 @@ usage. See also the
 
    
 
    
 The generated bytecode is portable and can be loaded on any architecture
-that LuaJIT supports, independent of word size or endianess. However the
+that LuaJIT supports, independent of word size or endianess. However, the
 bytecode compatibility versions must match. Bytecode stays compatible
 for dot releases (x.y.0 → x.y.1), but may change with major or
 minor releases (2.0 → 2.1) or between any beta release. Foreign
@@ -197,7 +197,7 @@ bytecode (e.g. from Lua 5.1) is incompatible and cannot be loaded.
 LuaJIT uses a Tausworthe PRNG with period 2^223 to implement
 math.random() and math.randomseed(). The quality of
 the PRNG results is much superior compared to the standard Lua
-implementation which uses the platform-specific ANSI rand().
+implementation, which uses the platform-specific ANSI rand().
 
    
 
    
 The PRNG generates the same sequences from the same seeds on all
@@ -215,7 +215,7 @@ Important: Neither this nor any other PRNG based on the simplistic
 
    io.* functions handle 64 bit file offsets
    
 
    
 The file I/O functions in the standard io.* library handle
-64 bit file offsets. In particular this means it's possible
+64 bit file offsets. In particular, this means it's possible
 to open files larger than 2 Gigabytes and to reposition or obtain
 the current file position for offsets beyond 2 GB
 (fp:seek() method).
diff --git a/doc/faq.html b/doc/faq.html
index 36b2eafc..0b4b2df0 100644
--- a/doc/faq.html
+++ b/doc/faq.html
@@ -116,7 +116,7 @@ Direct3D version 10 or higher do not show this behavior anymore.
 Consider testing your application with older versions, too.
    
 
 Similarly, the Borland/Delphi runtime modifies the FPU control word and
-enables FP exceptions. Of course this violates the Windows ABI, too.
+enables FP exceptions. Of course, this violates the Windows ABI, too.
 Please check the Delphi docs for the Set8087CW method.
 
 
@@ -126,7 +126,7 @@ Please check the Delphi docs for the Set8087CW method.
 ignored by compiled code. If your program is running in a tight loop
 and never falls back to the interpreter, the debug hook never runs and
 can't throw the "interrupted!" error.
    
-You have to press Ctrl-C twice to get stop your program. That's similar
+You have to press Ctrl-C twice to stop your program. That's similar
 to when it's stuck running inside a C function under the Lua interpreter.
 
 
@@ -146,7 +146,7 @@ so it doesn't rely on the key order. Or sort the table keys, if you must.
 
    
 
    Q: Can Lua code be safely sandboxed?
    
 
    
-Maybe for an extremly restricted subset of Lua and if you relentlessly
+Maybe for an extremely restricted subset of Lua and if you relentlessly
 scrutinize every single interface function you offer to the untrusted code.
    
 
 Although Lua provides some sandboxing functionality (setfenv(), hooks),
diff --git a/doc/install.html b/doc/install.html
index 19fab1b8..fe89fc5c 100644
--- a/doc/install.html
+++ b/doc/install.html
@@ -317,7 +317,7 @@ The recommended way to fetch the latest version is to do a pull from
 the git repository.
 
    
 
    
-Alternatively download the latest source package of LuaJIT (pick the .tar.gz).
+Alternatively, download the latest source package of LuaJIT (pick the .tar.gz).
 Move it to a directory of your choice, open a terminal window and change
 to this directory. Now unpack the archive and change to the newly created
 directory (replace XX.YY.ZZ with the version you downloaded):
@@ -475,7 +475,7 @@ important to compile with the proper CPU or architecture settings. You
 can specify these when building the toolchain yourself. Or add
 -mcpu=... or -march=... to TARGET_CFLAGS. For
 ARM it's important to have the correct -mfloat-abi=... setting,
-too. Otherwise LuaJIT may not run at the full performance of your target
+too. Otherwise, LuaJIT may not run at the full performance of your target
 CPU.
 
    
 
    @@ -619,7 +619,7 @@ allocator from your system (no support for this on 64 bit architectures).luaopen_base etc. directly.
  • To change or extend the list of standard libraries to load, copy src/lib_init.c to your project and modify it accordingly. -Make sure the jit library is loaded or the JIT compiler +Make sure the jit library is loaded, or the JIT compiler will not be activated.
  • The bit.* module for bitwise operations is already built-in. There's no need to statically link @@ -638,7 +638,7 @@ in unspeakable ways. There should be absolutely no need to patch luaconf.h or any of the Makefiles. And please do not hand-pick files for your packages — simply use whatever make install creates. There's a reason -for all of the files and directories it creates. +for all the files and directories it creates.

    The build system uses GNU make and auto-detects most settings based on diff --git a/doc/running.html b/doc/running.html index 2ce02bc4..3f408141 100644 --- a/doc/running.html +++ b/doc/running.html @@ -179,7 +179,7 @@ written in Lua. They are mainly used for debugging the JIT compiler itself. For a description of their options and output format, please read the comment block at the start of their source. They can be found in the lib directory of the source -distribution or installed under the jit directory. By default +distribution or installed under the jit directory. By default, this is /usr/local/share/luajit-XX.YY.ZZ>/jit on POSIX systems (replace XX.YY.ZZ by the installed version).

    @@ -211,7 +211,7 @@ to a specific value. You can either use this option multiple times (like -Ocse -O-dce -Ohotloop=10) or separate several settings with a comma (like -O+cse,-dce,hotloop=10). The settings are applied from -left to right and later settings override earlier ones. You can freely +left to right, and later settings override earlier ones. You can freely mix the three forms, but note that setting an optimization level overrides all earlier flags.

    diff --git a/doc/status.html b/doc/status.html index c251d224..7ecedf3d 100644 --- a/doc/status.html +++ b/doc/status.html @@ -79,7 +79,7 @@ Known incompatibilities and issues in LuaJIT 2.0: