From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id E1D323858C62; Sat, 22 Oct 2022 12:57:33 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E1D323858C62 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1666443453; bh=1C7AQBs4KKNIdftiNA2sCyUgaT8lyvsRMd5E38FfpDg=; h=From:To:Subject:Date:From; b=RLdGONMi3YBS3FFV3+WKXltZsAZsCM4Uf9zltTcK0ATjVzEGYLYHe/fG23sVBwzri HjP6h5LlHWanlIQF3FgJX/M6B1zZ63NOyZoISVMcdIQsh6LByF2ZL7CM5yNyBwuh4F gdQFxrnxo+06RFxqLZ3ab3/dKnSMAitDz0kQK18Q= From: "slyfox at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/107358] New: [13 Regression] i686-linux: Since r13-3290-g98e341130f8798 code fails to build libjxl-0/7.0 (vector float code) Date: Sat, 22 Oct 2022 12:57:32 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c++ X-Bugzilla-Version: 13.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: slyfox at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter cc target_milestone Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107358 Bug ID: 107358 Summary: [13 Regression] i686-linux: Since r13-3290-g98e341130f8798 code fails to build libjxl-0/7.0 (vector float code) Product: gcc Version: 13.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: slyfox at gcc dot gnu.org CC: jakub at gcc dot gnu.org, jakub at redhat dot com Target Milestone: --- Initially observed build failure on libjxl-0.7.0 on i686-linux target. Seems to happen only on i686-unknown-linux-gnu and only on -std=3Dc++11. PR107295 does not seem to be enough to fix it. Here is the minimal example: // $ cat skcms.cc // this works: float approx_scal(float e) { return e - 124.225514990f; } typedef float __attribute__((vector_size(4*sizeof(float)))) F; // this fails: // error: conversion of scalar 'long double' to vector 'F' {aka '__vector= (4) float'} involves truncation F approx_vec(F e) { return e - 124.225514990f; //return e - 1.0f; // this works, does 'f' get ignored when float does = not fit? } $ g++-13 -fPIC -std=3Dc++11 -o skcms.cc.o -c skcms.cc skcms.cc: In function 'F approx_vec(F)': skcms.cc:10:17: warning: SSE vector return without SSE enabled changes the = ABI [-Wpsabi] 10 | F approx_vec(F e) { | ^ skcms.cc:11:14: error: conversion of scalar 'long double' to vector 'F' {aka '__vector(4) float'} involves truncation 11 | return e - 124.225514990f; | ~~^~~~~~~~~~~~~~~~ $ g++-12 -fPIC -std=3Dc++11 -o skcms.cc.o -c skcms.cc skcms.cc: In function 'F approx_vec(F)': skcms.cc:10:17: warning: SSE vector return without SSE enabled changes the = ABI [-Wpsabi] 10 | F approx_vec(F e) { | ^ skcms.cc:10:3: note: the ABI for passing parameters with 16-byte alignment = has changed in GCC 4.6 10 | F approx_vec(F e) { | ^~~~~~~~~~ skcms.cc:10:3: warning: SSE vector argument without SSE enabled changes the= ABI=20 Note: gcc-12 works, gcc-13 fails.=