Bug 906018

Summary:	x11-libs/gtk+-2.24.33-r2: gdkalias.h:12:5: warning: macro expansion producing 'defined' has undefined behavior [-Wexpansion-to-defined]
Product:	Gentoo Linux	Reporter:	nvinson234
Component:	Current packages	Assignee:	Gentoo Linux Gnome Desktop Team <gnome>
Status:	UNCONFIRMED ---
Severity:	normal	Keywords:	PATCH
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---
Attachments:	cpp_macro_fix.patch

Description nvinson234 2023-05-09 11:57:53 UTC

When building with clang-16, this warning appears many times in the build log. The warning is correct; however, it appears so frequently that it makes finding the actual build error more difficult given the noise.

Reproducible: Always

Steps to Reproduce:
1. Build the library with clang-16
2. Observe the frequent undefined behavior warning messages.
Actual Results:  
Many undefined behavior warning messages appear.

Expected Results:  
Ideally, no warning messages.

The request isn't to fix every warning as gtk+-2 is an essentially dead package. However, removing these warnings could make diagnosing future build failures easier.

Comment 1 nvinson234 2023-05-09 11:59:18 UTC

Created attachment 861386 [details, diff]
cpp_macro_fix.patch

Updates the perl scripts responsible for the noisy undefined error warnings to generate the code in a different manner that prevents the warnings.