Bug 863290

Summary:	sci-visualization/gr-0.53.0 fails to compile (lto): <built-in>: error: type of __builtin_sqrtf does not match original declaration [-Werror=lto-type-mismatch]
Product:	Gentoo Linux	Reporter:	Agostino Sarubbo <ago>
Component:	Current packages	Assignee:	Andreas K. Hüttel <dilfridge>
Status:	RESOLVED FIXED
Severity:	normal	CC:	eschwartz
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---
Bug Depends on:
Bug Blocks:	618550
Attachments:	build.log

Description Agostino Sarubbo gentoo-dev

2022-08-03 07:09:03 UTC

https://blogs.gentoo.org/ago/2020/07/04/gentoo-tinderbox/

Issue: sci-visualization/gr-0.53.0 fails to compile (lto).
Discovered on: amd64 (internal ref: lto_tinderbox)

NOTE:
This machine uses lto with CFLAGS=-flto -Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing

Here is a bit of explanation:

-Werror=lto-type-mismatch:
User to find possible runtime issues in packages. It likely means the package is unsafe to build & use with LTO.
For projects using the same identifier but with different types across different files, they must be fixed to be consistent across the codebase.

-Werror=odr:
Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO. C++ code must comply with the One Definition Rule (ODR) - see https://en.cppreference.com/w/cpp/language/definition#One_Definition_Rule.

-Werror=strict-aliasing:
Used to find possible runtime issues in packages. These bugs are a problem anyway but may be even worse when combined with LTO.

Workarounds:
- If upstream is friendly and still active, file a bug upstream. For emulators, codecs, games, or multimedia packages, it may be worth just applying a workaround instead, as upstreams sometimes aren't receptive to these bugs (VALID FOR ALL).
- Use the new 'filter-lto' from flag-o-matic.eclass as it's likely to be unsafe with LTO (VALID FOR lto-type-mismatch - odr).
- Fix it yourself if interested, of course (VALID FOR ALL).
- Append-flags -fno-strict-aliasing (VALID FOR strict-aliasing).
- Use memcpy() but a union is sometimes suitable too (VALID FOR strict-aliasing).
- -fstrict-aliasing is implied by -O2, so this must be addressed in some form (VALID FOR strict-aliasing).

See also: https://marc.info/?l=gentoo-dev&m=165639574126280&w=2

Comment 1 Agostino Sarubbo gentoo-dev

2022-08-03 07:09:06 UTC

Created attachment 797161 [details]
build.log

build log and emerge --info

Comment 2 Agostino Sarubbo gentoo-dev

2022-08-03 07:09:08 UTC

Error(s) that match a know pattern in addition to what has been reported in the summary:


-- Could NOT find Cairo (missing: CAIRO_LIBRARY) (found version "1.16.0")
-- Could NOT find Ffmpeg (missing: FFMPEG_TEST_COMPILED FFMPEG_LIBRARY_AVFORMAT FFMPEG_LIBRARY_AVCODEC FFMPEG_LIBRARY_SWSCALE FFMPEG_LIBRARY_AVUTIL) (Required is at least version "57.48.100")
-- Could NOT find Freetype (missing: FREETYPE_LIBRARY) (found version "2.12.1")
-- Could NOT find Gs (missing: GS_LIBRARY GS_INCLUDE_DIR GS_VERSION_STRING) 
-- Could NOT find Qt5Network (missing: Qt5Network_DIR)
-- Could NOT find Qt5Widgets (missing: Qt5Widgets_DIR)
-- Could NOT find Tiff (missing: TIFF_LIBRARY TIFF_INCLUDE_DIR TIFF_VERSION_STRING) 
-- Could NOT find Zeromq (missing: ZEROMQ_LIBRARY ZEROMQ_INCLUDE_DIR ZEROMQ_VERSION_STRING) (Required is exact version "4.0")
FAILED: libGR3.so 
<built-in>: error: type of ‘__builtin_sqrtf’ does not match original declaration [-Werror=lto-type-mismatch]

Comment 3 Eli Schwartz gentoo-dev

2024-03-07 03:32:23 UTC

This no longer occurs in sci-visualization/gr-0.72.4