diff --git a/lxterminal.spec b/lxterminal.spec
index 255ac7f..2a5686e 100644
--- a/lxterminal.spec
+++ b/lxterminal.spec
@@ -19,7 +19,7 @@
 
 Name:           lxterminal
 Version:        0.4.0
-Release:        2%{?gitversion:.%{?gitversion}}%{?dist}
+Release:        3%{?gitversion:.%{?gitversion}}%{?dist}
 Summary:        Desktop-independent VTE-based terminal emulator
 Summary(de):    Desktop-unabhängiger VTE-basierter Terminal Emulator
 
@@ -95,6 +95,9 @@ cp -a [A-Z]* ..
 %endif
 
 %build
+%global optflags_orig %optflags
+%global optflags %optflags_orig -fno-optimize-sibling-calls
+
 %if 0%{?git_snapshot}
 cd %{name}
 sh autogen.sh
@@ -144,6 +147,10 @@ cd ..
 
 
 %changelog
+* Fri Nov  5 2021 Mamoru TASAKA <mtasaka@fedoraproject.org> - 0.4.0-3
+- Disable call instruction optimization to jmp for debugging
+  (c.f. bug 2016637)
+
 * Thu Jul 22 2021 Fedora Release Engineering <releng@fedoraproject.org> - 0.4.0-2
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_35_Mass_Rebuild