[Emacs-diffs] trunk r113054: * conf_post.h: Add comments for INLINE, EXTERN_INLINE, etc.

[Paul Eggert]

------------------------------------------------------------
revno: 113054
revision-id: address@hidden
parent: address@hidden
committer: Paul Eggert <address@hidden>
branch nick: trunk
timestamp: Tue 2013-06-18 11:36:13 -0700
message:
  * conf_post.h: Add comments for INLINE, EXTERN_INLINE, etc.
modified:
  src/ChangeLog                  changelog-20091113204419-o5vbwnq5f7feedwu-1438
  src/conf_post.h                conf_post.h-20120730211826-q0qbxxwh2emw52hd-1

=== modified file 'src/ChangeLog'
--- a/src/ChangeLog     2013-06-18 14:54:48 +0000
+++ b/src/ChangeLog     2013-06-18 18:36:13 +0000
@@ -1,3 +1,7 @@
+2013-06-18  Paul Eggert  <address@hidden>
+
+       * conf_post.h: Add comments for INLINE, EXTERN_INLINE, etc.
+
 2013-06-18  Kenichi Handa  <address@hidden>
 
        * font.c (Ffont_spec): Signal an error for an invalid font name

=== modified file 'src/conf_post.h'
--- a/src/conf_post.h   2013-03-13 18:42:22 +0000
+++ b/src/conf_post.h   2013-06-18 18:36:13 +0000
@@ -207,6 +207,37 @@
 #undef noinline
 #endif
 
+/* Use Gnulib's extern-inline module for extern inline functions.
+   An include file foo.h should prepend FOO_INLINE to function
+   definitions, with the following overall pattern:
+
+      [#include any other .h files first.]
+      ...
+      INLINE_HEADER_BEGIN
+      #ifndef FOO_INLINE
+      # define FOO_INLINE INLINE
+      #endif
+      ...
+      FOO_INLINE int
+      incr (int i)
+      {
+        return i + 1;
+      }
+      ...
+      INLINE_HEADER_END
+
+   The corresponding foo.c file should do this:
+
+      #define FOO_INLINE EXTERN_INLINE
+
+   before including any .h file other than config.h.
+   Other .c files should not define FOO_INILNE.
+
+   C99 compilers compile functions like 'incr' as C99-style extern
+   inline functions.  Pre-C99 GCCs do something similar with
+   GNU-specific keywords.  Pre-C99 non-GCC compilers use static
+   functions, which bloats the code but is good enough.  */
+
 #define INLINE _GL_INLINE
 #define EXTERN_INLINE _GL_EXTERN_INLINE
 #define INLINE_HEADER_BEGIN _GL_INLINE_HEADER_BEGIN