Provide DLLEXPORT markers for C functions via PG_FUNCTION_INFO_V1 macro.

Second try at the change originally made in commit 8518583cd;
this time with contrib updates so that manual extern declarations
are also marked with PGDLLEXPORT.  The release notes should point
this out as a significant source-code change for extension authors,
since they'll have to make similar additions to avoid trouble on Windows.

Laurenz Albe, doc change by me

Patch: <A737B7A37273E048B164557ADEF4A58B53962ED8@ntex2010a.host.magwien.gv.at>

diff --git a/contrib/hstore/hstore.h b/contrib/hstore/hstore.h
index 6bab08b7de0b8028f416b1a38ff6a495d0b12a88..6303fa406192e62d80800c9590c4bb022c077368 100644 (file)
--- a/contrib/hstore/hstore.h
+++ b/contrib/hstore/hstore.h
@@ -194,7 +194,7 @@ extern Pairs *hstoreArrayToPairs(ArrayType *a, int *npairs);
 #if HSTORE_POLLUTE_NAMESPACE
 #define HSTORE_POLLUTE(newname_,oldname_) \
        PG_FUNCTION_INFO_V1(oldname_);            \
-       Datum newname_(PG_FUNCTION_ARGS);         \
+       extern PGDLLEXPORT Datum newname_(PG_FUNCTION_ARGS); \
        Datum oldname_(PG_FUNCTION_ARGS) { return newname_(fcinfo); } \
        extern int no_such_variable
 #else

diff --git a/contrib/ltree/ltree.h b/contrib/ltree/ltree.h
index c604357dbfbb215ced194ed801fbe90247dd62d5..c7aa7f881889f6e78368ebe2f74208e6cfdfc85d 100644 (file)
--- a/contrib/ltree/ltree.h
+++ b/contrib/ltree/ltree.h
@@ -130,30 +130,30 @@ typedef struct
 
 
 /* use in array iterator */
-Datum          ltree_isparent(PG_FUNCTION_ARGS);
-Datum          ltree_risparent(PG_FUNCTION_ARGS);
-Datum          ltq_regex(PG_FUNCTION_ARGS);
-Datum          ltq_rregex(PG_FUNCTION_ARGS);
-Datum          lt_q_regex(PG_FUNCTION_ARGS);
-Datum          lt_q_rregex(PG_FUNCTION_ARGS);
-Datum          ltxtq_exec(PG_FUNCTION_ARGS);
-Datum          ltxtq_rexec(PG_FUNCTION_ARGS);
-Datum          _ltq_regex(PG_FUNCTION_ARGS);
-Datum          _ltq_rregex(PG_FUNCTION_ARGS);
-Datum          _lt_q_regex(PG_FUNCTION_ARGS);
-Datum          _lt_q_rregex(PG_FUNCTION_ARGS);
-Datum          _ltxtq_exec(PG_FUNCTION_ARGS);
-Datum          _ltxtq_rexec(PG_FUNCTION_ARGS);
-Datum          _ltree_isparent(PG_FUNCTION_ARGS);
-Datum          _ltree_risparent(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltree_isparent(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltree_risparent(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltq_regex(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltq_rregex(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum lt_q_regex(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum lt_q_rregex(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltxtq_exec(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltxtq_rexec(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum _ltq_regex(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum _ltq_rregex(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum _lt_q_regex(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum _lt_q_rregex(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum _ltxtq_exec(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum _ltxtq_rexec(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum _ltree_isparent(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum _ltree_risparent(PG_FUNCTION_ARGS);
 
 /* Concatenation functions */
-Datum          ltree_addltree(PG_FUNCTION_ARGS);
-Datum          ltree_addtext(PG_FUNCTION_ARGS);
-Datum          ltree_textadd(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltree_addltree(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltree_addtext(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltree_textadd(PG_FUNCTION_ARGS);
 
 /* Util function */
-Datum          ltree_in(PG_FUNCTION_ARGS);
+extern PGDLLEXPORT Datum ltree_in(PG_FUNCTION_ARGS);
 
 bool ltree_execute(ITEM *curitem, void *checkval,
                          bool calcnot, bool (*chkcond) (void *checkval, ITEM *val));

diff --git a/doc/src/sgml/xfunc.sgml b/doc/src/sgml/xfunc.sgml
index de6a466efc587cce7096ea588f22c4082ef7c359..6060e618576ffa0b0816124b15c4309c1b3da13b 100644 (file)
--- a/doc/src/sgml/xfunc.sgml
+++ b/doc/src/sgml/xfunc.sgml
@@ -2577,6 +2577,23 @@ concat_text(PG_FUNCTION_ARGS)
         error messages to this effect.
        </para>
       </listitem>
+
+      <listitem>
+       <para>
+        To work correctly on Windows, <literal>C</>-language functions need
+        to be marked with <literal>PGDLLEXPORT</>, unless you use a build
+        process that marks all global functions that way.  In simple cases
+        this detail will be handled transparently by
+        the <literal>PG_FUNCTION_INFO_V1</> macro.  However, if you write
+        explicit external declarations (perhaps in header files), be sure
+        to write them like this:
+<programlisting>
+extern PGDLLEXPORT Datum funcname(PG_FUNCTION_ARGS);
+</programlisting>
+        or you'll get compiler complaints when building on Windows.  (On
+        other platforms, the <literal>PGDLLEXPORT</> macro does nothing.)
+       </para>
+      </listitem>
      </itemizedlist>
     </para>
    </sect2>

diff --git a/src/include/fmgr.h b/src/include/fmgr.h
index 0878418516e2d48b05869f527984f4e5191d9fff..3668ac3f6e946566edbb9de085b5677cf82a8ac2 100644 (file)
--- a/src/include/fmgr.h
+++ b/src/include/fmgr.h
@@ -350,12 +350,11 @@ typedef const Pg_finfo_record *(*PGFInfoFunction) (void);
  *
  *     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.
- *     Module authors using a different build process might need to manually
- *     declare the function PGDLLEXPORT.  We do that automatically here for the
- *     info function, since authors shouldn't need to be explicitly aware of it.
+ *     Module authors using a different build process might do it differently,
+ *     so we declare these functions PGDLLEXPORT for their convenience.
  */
 #define PG_FUNCTION_INFO_V1(funcname) \
-extern 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) \