From a24d9b5bbb6a298ff4e55d731d5e436b0da9e38a Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Tue, 19 May 2020 08:36:13 +0200 Subject: [PATCH] lto/95190 - amend -flto docs for diagnostic option handling This documents new GCC 10 behavior on diagnostic options and -flto. 2020-05-22 Richard Biener PR lto/95190 * doc/invoke.texi (flto): Document behavior of diagnostic options. (cherry picked from commit ab7eca92926fdc1da880120c116a1832fce56a29) --- gcc/ChangeLog | 6 ++++++ gcc/doc/invoke.texi | 8 ++++++++ 2 files changed, 14 insertions(+) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 076b8f4c9063..1e2f466b17d3 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2020-05-22 Richard Biener + + PR lto/95190 + * doc/invoke.texi (flto): Document behavior of diagnostic + options. + 2020-05-21 Uroš Bizjak PR target/95169 diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index f98161391a09..539d848f2f83 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -11204,6 +11204,14 @@ conflicting translation units. Specifically precedence; and for example @option{-ffp-contract=off} takes precedence over @option{-ffp-contract=fast}. You can override them at link time. +Diagnostic options such as @option{-Wstringop-overflow} are passed +through to the link stage and their setting matches that of the +compile-step at function granularity. Note that this matters only +for diagnostics emitted during optimization. Note that code +transforms such as inlining can lead to warnings being enabled +or disabled for regions if code not consistent with the setting +at compile time. + When you need to pass options to the assembler via @option{-Wa} or @option{-Xassembler} make sure to either compile such translation units with @option{-fno-lto} or consistently use the same assembler -- 2.47.2