blocks|key|70946|text|<machine/endian.h>失败的原因是，当你包装一个文件来包装它的接口时，它通常不会递归到包含文件中，所以SWIG中定义的定义不会被处理。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|70947|有许多选项可以解决此问题：|70948|70949|使用-cpperraswarn并按照建议忽略错误。这通常是不需要的，因为SWIG将尝试包装所有定义。例如，如果present.|ordered-list-item|70950|Explicitly在SWIG+.i文件中定义BYTE_ORDER和/或LITTLE_ENDIAN来解决此问题，您将获得#include+<stdio.h>中的所有内容。|70951|70952|这里有几个例子：|70953|--cpperraswarn解决方案：|70954|test.i|70955|%25module+test

%25{
#include+"test.h"
%25}

%25include+"test.h"|code-block|syntax|javascript|70956|SWIG生成警告，结果是只定义了HIOFFSET和LOWOFFSET，但它们对于我的小端机器是正确的，即使有来自SWIG的错误。编译器仍然正确地处理了定义。|70957|>>>+import+test
>>>+dir(test)
['HIOFFSET',+'LOWOFFSET',+'SWIG_PyInstanceMethod_New',+'__builtin__',+'__builtins__',+'__cached__',+'__doc__',+'__file__',+'__loader__',+'__name__',+'__package__',+'__spec__',+'_swig_getattr',+'_swig_property',+'_swig_repr',+'_swig_setattr',+'_swig_setattr_nondynamic',+'_swig_setattr_nondynamic_method',+'_test']
>>>+test.HIOFFSET
1|70958|70959|70960|test.h已修改为使用以下代码段：|BOLD|70961|#ifdef+_MSC_VER
#include+"msvc_endian.h"
#endif|70962|test.i显式处理了报头：|70963|%25module+test

%25{
#include+"test.h"
%25}

%25include+"msvc_endian.h"
%25include+"test.h"|70964|msvc_endian.h|70965|#define+LITTLE_ENDIAN+0x0001
#define+BYTE_ORDER+LITTLE_ENDIAN|70966|SWIG现在没有警告，结果仍然正确，但由于处理过程，子头LITTLE_ENDIAN和BYTE_ORDER也在包装器中公开为值：|70967|>>>+import+test
>>>+dir(test)
['BYTE_ORDER',+'HIOFFSET',+'LITTLE_ENDIAN',+'LOWOFFSET',+'SWIG_PyInstanceMethod_New',+'__builtin__',+'__builtins__',+'__cached__',+'__doc__',+'__file__',+'__loader__',+'__name__',+'__package__',+'__spec__',+'_swig_getattr',+'_swig_property',+'_swig_repr',+'_swig_setattr',+'_swig_setattr_nondynamic',+'_swig_setattr_nondynamic_method',+'_test']
>>>+test.HIOFFSET
1|70968|entityMap^0|0|I|0|0|0|2|D|0|N|A|10|D|1O|I|0|0|0|0|0|0|G|8|P|9|0|0|0|0|0|6|0|0|0|6|0|0|0|D|0|0|S|D|16|A|0|0^^$0|@$1|2|3|4|5|6|7|1O|8|@$9|1P|A|1Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1R|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|1S|8|@]|D|@]|E|$]]|$1|I|3|J|5|K|7|1T|8|@$9|1U|A|1V|B|C]]|D|@]|E|$]]|$1|L|3|M|5|K|7|1W|8|@$9|1X|A|1Y|B|C]|$9|1Z|A|20|B|C]|$9|21|A|22|B|C]]|D|@]|E|$]]|$1|N|3|-4|5|6|7|23|8|@]|D|@]|E|$]]|$1|O|3|P|5|6|7|24|8|@]|D|@]|E|$]]|$1|Q|3|R|5|6|7|25|8|@]|D|@]|E|$]]|$1|S|3|T|5|6|7|26|8|@]|D|@]|E|$]]|$1|U|3|V|5|W|7|27|8|@]|D|@]|E|$X|Y]]|$1|Z|3|10|5|6|7|28|8|@$9|29|A|2A|B|C]|$9|2B|A|2C|B|C]]|D|@]|E|$]]|$1|11|3|12|5|W|7|2D|8|@]|D|@]|E|$X|Y]]|$1|13|3|-4|5|6|7|2E|8|@]|D|@]|E|$]]|$1|14|3|-4|5|6|7|2F|8|@]|D|@]|E|$]]|$1|15|3|16|5|6|7|2G|8|@$9|2H|A|2I|B|17]]|D|@]|E|$]]|$1|18|3|19|5|W|7|2J|8|@]|D|@]|E|$X|Y]]|$1|1A|3|1B|5|6|7|2K|8|@$9|2L|A|2M|B|17]]|D|@]|E|$]]|$1|1C|3|1D|5|W|7|2N|8|@]|D|@]|E|$X|Y]]|$1|1E|3|1F|5|6|7|2O|8|@$9|2P|A|2Q|B|17]]|D|@]|E|$]]|$1|1G|3|1H|5|W|7|2R|8|@]|D|@]|E|$X|Y]]|$1|1I|3|1J|5|6|7|2S|8|@$9|2T|A|2U|B|C]|$9|2V|A|2W|B|C]]|D|@]|E|$]]|$1|1K|3|1L|5|W|7|2X|8|@]|D|@]|E|$X|Y]]|$1|1M|3|-4|5|6|7|2Y|8|@]|D|@]|E|$]]]|1N|$]]

The reason SWIG is failing is because it doesn't normally recurse into include files when you <code>%include</code> a file to wrap its interface, so the definitions defined in <code>&lt;machine/endian.h&gt;</code> are not processed.

There are a number of options to remedy this:

<ol>
<li>Use <code>-cpperraswarn</code> and ignore the error as suggested. SWIG will process the #if incorrectly, but it is the compiler that builds the value. SWIG will still expose the <code>HIOFFSET</code> and <code>LOWOFFSET</code> values in the wrapper, and the value will be correct.</li>
<li><code>%include &lt;machine/endian.h&gt;</code> explicitly. That may or may not work correctly depending on the content of the file, and may expose more variables in the SWIG wrapper than intended.</li>
<li>Use <code>-includeall</code> with SWIG to explicitly recurse into all #include files. This is normally not wanted as SWIG will attempt to wrap all definitions. For example, you'd get everything in <code>#include &lt;stdio.h&gt;</code> if present.</li>
<li>Explicitly define <code>BYTE_ORDER</code> and/or <code>LITTLE_ENDIAN</code> in the SWIG .i file to work around the issue.</li>
</ol>

Here's a couple of examples:

<h2>--cpperraswarn Solution:</h2>

<h3>test.i</h3>

<pre><code>%module test

%{
#include "test.h"
%}

%include "test.h"
</code></pre>

SWIG generates the warning, and the result is only <code>HIOFFSET</code> and <code>LOWOFFSET</code> are defined, but they are correct for my little-endian machine even with the error from SWIG. The compiler still processed the definition correctly.

<pre><code>&gt;&gt;&gt; import test
&gt;&gt;&gt; dir(test)
['HIOFFSET', 'LOWOFFSET', 'SWIG_PyInstanceMethod_New', '__builtin__', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__', '_swig_getattr', '_swig_property', '_swig_repr', '_swig_setattr', '_swig_setattr_nondynamic', '_swig_setattr_nondynamic_method', '_test']
&gt;&gt;&gt; test.HIOFFSET
1
</code></pre>

<h2>%include endian.h Solution:</h2>

In this case I have a Windows machine so I simulated the problem by creating an <code>msvc_endian.h</code> file and defining <code>BYTE_ORDER</code> and <code>LITTLE_ENDIAN</code> in it.

test.h was modified to use the following snippet:

<pre><code>#ifdef _MSC_VER
#include "msvc_endian.h"
#endif
</code></pre>

test.i explicitly processed the header:

<pre><code>%module test

%{
#include "test.h"
%}

%include "msvc_endian.h"
%include "test.h"
</code></pre>

msvc_endian.h

<pre><code>#define LITTLE_ENDIAN 0x0001
#define BYTE_ORDER LITTLE_ENDIAN
</code></pre>

SWIG now has no warning and the result is still correct, but due to processing the sub-header <code>LITTLE_ENDIAN</code> and <code>BYTE_ORDER</code> were also exposed as values in the wrapper:

<pre><code>&gt;&gt;&gt; import test
&gt;&gt;&gt; dir(test)
['BYTE_ORDER', 'HIOFFSET', 'LITTLE_ENDIAN', 'LOWOFFSET', 'SWIG_PyInstanceMethod_New', '__builtin__', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__', '_swig_getattr', '_swig_property', '_swig_repr', '_swig_setattr', '_swig_setattr_nondynamic', '_swig_setattr_nondynamic_method', '_test']
&gt;&gt;&gt; test.HIOFFSET
1
</code></pre>

Here's my preprocessor section in my C++ code which I want to generate SWIG bindings.
<pre class="lang-c prettyprint-override"><code>#if defined(__FreeBSD__) || defined(__APPLE__) || defined(__FreeBSD_kernel__) \
|| defined(__OpenBSD__)
#include &lt;machine/endian.h&gt;
#endif
 
#if defined(__linux__) || defined(__CYGWIN__) || defined(__GNU__) || \
defined(ANDROID)
#include &lt;endian.h&gt;
#endif
 
#ifdef __MINGW32__
#include &lt;sys/param.h&gt;
#endif
 
#ifdef _MSC_VER
/* _MSVC lacks BYTE_ORDER and LITTLE_ENDIAN */
#define LITTLE_ENDIAN 0x0001
#define BYTE_ORDER LITTLE_ENDIAN
#endif
 
#if !defined(BYTE_ORDER) || !defined(LITTLE_ENDIAN)
#error No byte order defined
#endif
 
#if BYTE_ORDER == LITTLE_ENDIAN
# define HIOFFSET 1
# define LOWOFFSET 0
#else
# define HIOFFSET 0 /* word offset to find MSB */
# define LOWOFFSET 1 /* word offset to find LSB */
#endif
</code></pre>
But when I try to generate SWIG bindings using the <code>swig</code> command, I get the following error:
<blockquote>
Error: CPP #error &quot;No byte order defined&quot;. Use the -cpperraswarn
option to continue swig processing.
</blockquote>
It seems when SWIG tries to generate the bindings, <code>&lt;machine/endian.h&gt;</code> is not being included for some reasons.
How can I fix this error? Do I need to add anything to the SWIG interface file?
I'm using macOS 10.14.4.
<hr />
ADDED: Here's what my SWIG interface file looks like.
<pre><code>%module pd
%{
 #include &quot;myBindings.h&quot;
%}
%include &quot;myBindings.h&quot;
</code></pre>
As you can see there's nothing special in it.
And I generate the bindings using the following command:
<pre><code>swig -c++ -lua -fcompact -fvirtual -I../../../libs/openFrameworks myBindings.i &amp;&amp; mv myBindings_wrap.cxx myBindings.cpp
</code></pre>
Then I get the above mentioned error.
Even when I just leave <code>#include &lt;machine/endian.h&gt;</code> it still generates the same error. (<code>No byte order defined</code>)

Cannot include <endian.h> when generating SWIG bindings

编译器

下面是我的C++代码中的预处理器部分，我希望生成SWIG绑定。#if defined(__FreeBSD__) || defined(__APPLE__) || defined(__FreeBSD_kernel__) \|| defined(__OpenBSD__)#include <machine/endian.h>...

问生成SWIG绑定时不能包含<endian.h>
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