[goffice] Introspection: hack around --without-long-double problem.

[Morten Welinder <mortenw src gnome org>]

commit 8fb94bc63cfff0670939c64125229095ea37934f
Author: Morten Welinder <terra gnome org>
Date:   Wed Jul 6 15:37:40 2022 -0400

    Introspection: hack around --without-long-double problem.

 NEWS                      | 1 +
 goffice/math/go-complex.c | 5 +++++
 2 files changed, 6 insertions(+)
---
diff --git a/NEWS b/NEWS
index 3765e560..d9f66ccf 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,7 @@ goffice 0.10.53:
 
 Morten:
        * Fix problem rendering "...E-xx" numbers.  [#60]
+       * Hack around introspection issue.  [Part of #59]
 
 --------------------------------------------------------------------------
 goffice 0.10.52:
diff --git a/goffice/math/go-complex.c b/goffice/math/go-complex.c
index 1066a0a1..df203aa3 100644
--- a/goffice/math/go-complex.c
+++ b/goffice/math/go-complex.c
@@ -84,6 +84,11 @@ id (void)                                                            \
 MAKE_BOXED_TYPE(go_complexl_get_type, "GOComplexl")
 #else
 MAKE_BOXED_TYPE(go_complex_get_type, "GOComplex")
+#ifndef GOFFICE_WITH_LONG_DOUBLE
+// Hack for introspection
+GType go_complexl_get_type (void);
+GType go_complexl_get_type (void) { return 0; }
+#endif
 #endif
 
 /* ------------------------------------------------------------------------- */