From fe57410b33de1e8640091f0a1ac3ddde81163882 Mon Sep 17 00:00:00 2001 From: Linus Dierheimer Date: Wed, 22 Jun 2022 14:32:54 +0200 Subject: IPO: Use -flto=auto if compiler is GCC >= 10.1 Since GCC 12.1, the `-flto` option warns unless given an explicit LTRANS job count. Issue: #23640 --- Modules/Compiler/GNU.cmake | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/Modules/Compiler/GNU.cmake b/Modules/Compiler/GNU.cmake index c5946f0..db1eab5 100644 --- a/Modules/Compiler/GNU.cmake +++ b/Modules/Compiler/GNU.cmake @@ -72,7 +72,18 @@ macro(__compiler_gnu lang) # * https://gcc.gnu.org/onlinedocs/gcc-4.5.4/gcc/Option-Summary.html (yes) if(NOT CMAKE_${lang}_COMPILER_VERSION VERSION_LESS 4.5) set(_CMAKE_${lang}_IPO_MAY_BE_SUPPORTED_BY_COMPILER YES) - set(__lto_flags -flto) + + set(__lto_flags "") + + # '-flto=auto' introduced since GCC 10.1: + # * https://gcc.gnu.org/onlinedocs/gcc-9.5.0/gcc/Optimize-Options.html#Optimize-Options (no) + # * https://gcc.gnu.org/onlinedocs/gcc-10.1.0/gcc/Optimize-Options.html#Optimize-Options (yes) + # Since GCC 12.1, the abundance of a parameter produces a warning if compiling multiple targets. + if(NOT CMAKE_${lang}_COMPILER_VERSION VERSION_LESS 10.1) + list(APPEND __lto_flags -flto=auto) + else() + list(APPEND __lto_flags -flto) + endif() if(NOT CMAKE_${lang}_COMPILER_VERSION VERSION_LESS 4.7) # '-ffat-lto-objects' introduced since GCC 4.7: -- cgit v0.12