diff --git a/0001-scanner-Add-more-float-types.patch b/0001-scanner-Add-more-float-types.patch
new file mode 100644
index 0000000..8e1f001
--- /dev/null
+++ b/0001-scanner-Add-more-float-types.patch
@@ -0,0 +1,31 @@
+From 60b0cf2fc2fdc74d13832d1fdde21cfdc813b84e Mon Sep 17 00:00:00 2001
+From: Emmanuele Bassi <ebassi@gnome.org>
+Date: Mon, 26 Apr 2021 10:59:52 +0100
+Subject: [PATCH] scanner: Add more float types
+
+The scanner is chocking on the `__float80` and `__float128` types that
+are provided by GCC as extensions to ISO/IEC TS 18661-3:2015:
+
+https://gcc.gnu.org/onlinedocs/gcc/Floating-Types.html
+
+Fixes: #384
+---
+ giscanner/scannerlexer.l | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/giscanner/scannerlexer.l b/giscanner/scannerlexer.l
+index cfec4d58..b6cc6499 100644
+--- a/giscanner/scannerlexer.l
++++ b/giscanner/scannerlexer.l
+@@ -224,6 +224,8 @@ stringtext				([^\\\"])|(\\.)
+ "_Float32x"                             { return BASIC_TYPE; }
+ "_Float64x"                             { return BASIC_TYPE; }
+ "_Float128x"                            { return BASIC_TYPE; }
++"__float80"                             { return BASIC_TYPE; }
++"__float128"                            { return BASIC_TYPE; }
+ "for"					{ return FOR; }
+ "goto"					{ return GOTO; }
+ "if"					{ return IF; }
+-- 
+2.31.1
+
diff --git a/gobject-introspection.spec b/gobject-introspection.spec
index e5e269f..5336866 100644
--- a/gobject-introspection.spec
+++ b/gobject-introspection.spec
@@ -2,13 +2,15 @@
 
 Name:           gobject-introspection
 Version:        1.68.0
-Release:        2%{?dist}
+Release:        3%{?dist}
 Summary:        Introspection system for GObject-based libraries
 
 License:        GPLv2+, LGPLv2+, MIT
 URL:            https://wiki.gnome.org/Projects/GObjectIntrospection
 Source0:        https://download.gnome.org/sources/gobject-introspection/1.68/%{name}-%{version}.tar.xz
 
+Patch0:         0001-scanner-Add-more-float-types.patch
+
 BuildRequires:  gcc
 BuildRequires:  bison
 BuildRequires:  cairo-gobject-devel
@@ -53,6 +55,7 @@ Libraries and headers for gobject-introspection
 
 %prep
 %autosetup -p1
+%patch0 -p1 -b .float128
 
 %build
 %meson -Ddoctool=enabled -Dgtk_doc=true -Dpython=%{__python3}
@@ -84,6 +87,10 @@ Libraries and headers for gobject-introspection
 %{_mandir}/man1/g-ir-scanner.1*
 
 %changelog
+* Tue Apr 27 2010 Matthias Clasen <mclasen@redhat.com - 1.68.0-3
+- Add upstream patch to support __float128 as used in graphene
+- Related: rhbz#1915340
+
 * Thu Apr 15 2021 Mohan Boddu <mboddu@redhat.com> - 1.68.0-2
 - Rebuilt for RHEL 9 BETA on Apr 15th 2021. Related: rhbz#1947937