postgres.git / summary / log / commit / refs

commit    6298eaec86d86228dc59cb38fa7e69930598776d
Author:   Tom Lane <tgl@sss.pgh.pa.us>
Date:     Wed Oct 12 16:45:50 2016 +0000

    Provide DLLEXPORT markers for C functions via PG_FUNCTION_INFO_V1 macro.
    
    This isn't really necessary for our own code, because we use a .DEF file
    in MSVC builds (see gendef.pl), or --export-all-symbols in MinGW and
    Cygwin builds, to ensure that all global symbols in loadable modules
    will be exported on Windows.  However, third-party authors might use
    different build processes that need this marker, and it's harmless
    enough for our own builds.
    
    To some extent, this is an oversight in commit e7128e8db, so back-patch
    to 9.4 where that was added.
    
    Laurenz Albe
    
    Discussion: <A737B7A37273E048B164557ADEF4A58B539300BD@ntex2010a.host.magwien.gv.at>


 src/include/fmgr.h | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/include/fmgr.h b/src/include/fmgr.h
index 808d142bd4a..a15a1a2ebd0 100644
--- a/src/include/fmgr.h
+++ b/src/include/fmgr.h
@@ -344,11 +344,17 @@ typedef const Pg_finfo_record *(*PGFInfoFunction) (void);
 
 /*
  *	Macro to build an info function associated with the given function name.
- *	Win32 loadable functions usually link with 'dlltool --export-all', but it
- *	doesn't hurt to add PGDLLIMPORT in case they don't.
+ *
+ *	As a convenience, also provide an "extern" declaration for the given
+ *	function name, so that writers of C functions need not write that too.
+ *
+ *	On Windows, the function and info function must be exported.  Our normal
+ *	build processes take care of that via .DEF files or --export-all-symbols.
+ *	We add PGDLLEXPORT nonetheless so that C functions built with a
+ *	different build process are guaranteed to be exported.
  */
 #define PG_FUNCTION_INFO_V1(funcname) \
-Datum funcname(PG_FUNCTION_ARGS); \
+extern PGDLLEXPORT Datum funcname(PG_FUNCTION_ARGS); \
 extern PGDLLEXPORT const Pg_finfo_record * CppConcat(pg_finfo_,funcname)(void); \
 const Pg_finfo_record * \
 CppConcat(pg_finfo_,funcname) (void) \


[parent: e611b11634aa]