[gobject-introspection: 1/2] dumper: Fix missing symbols in LTO case or with overridden symbol visibility settings

[Christoph Reiter <creiter src gnome org>]

commit cea7ef1e4a5626de1332bc34e1962befb75c2976
Author: Christoph Reiter <reiter christoph gmail com>
Date:   Thu May 14 09:41:43 2020 +0200

    dumper: Fix missing symbols in LTO case or with overridden symbol visibility settings
    
    In case a user had a combination of -fvisibility=hidden, -Wl,--as-needed, -flto, -O2
    in the CFLAGS the linker would sometimes detect that all the referenced gtype functions
    weren't actually used and throw them out with their providing libraries.
    
    Instead of hoping that the user's CFLAGS don't mess without our symbol visibility just use
    G_MODULE_EXPORT on the two symbols which reference all other gtype and gquark symbols.
    
    This fixes errors such as:
    
    Invalid GType function: 'gtk_accel_group_get_type'
    Failed to find symbol 'gtk_accel_group_get_type'
    
    during the g-ir-scanner execution.
    
    Fixes #280

 giscanner/dumper.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/giscanner/dumper.py b/giscanner/dumper.py
index 0c10a780..e4b6ea03 100644
--- a/giscanner/dumper.py
+++ b/giscanner/dumper.py
@@ -126,7 +126,7 @@ class DumpCompiler(object):
             if len(self._get_type_functions) > 0:
                 for func in self._get_type_functions:
                     f.write("extern GType " + func + "(void);\n")
-                f.write("GType (*GI_GET_TYPE_FUNCS_[])(void) = {\n")
+                f.write("G_MODULE_EXPORT GType (*GI_GET_TYPE_FUNCS_[])(void) = {\n")
                 first = True
                 for func in self._get_type_functions:
                     if first:
@@ -138,7 +138,7 @@ class DumpCompiler(object):
             if len(self._error_quark_functions) > 0:
                 for func in self._error_quark_functions:
                     f.write("extern GQuark " + func + "(void);\n")
-                f.write("GQuark (*GI_ERROR_QUARK_FUNCS_[])(void) = {\n")
+                f.write("G_MODULE_EXPORT GQuark (*GI_ERROR_QUARK_FUNCS_[])(void) = {\n")
                 first = True
                 for func in self._error_quark_functions:
                     if first: