From 679e9d7c56e2296e3a218290d941e28002bf7722 Mon Sep 17 00:00:00 2001 From: Eli Zaretskii Date: Sat, 24 Jun 2023 10:23:07 +0300 Subject: [PATCH] ; Mention MinGW64 GCC 13.1 problems in PROBLEMS * etc/PROBLEMS: Mention the problems building with MinGW64 GCC 13.1. (Bug#63365) --- etc/PROBLEMS | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/etc/PROBLEMS b/etc/PROBLEMS index e5baa8ee18a..80b3b9945c4 100644 --- a/etc/PROBLEMS +++ b/etc/PROBLEMS @@ -3422,6 +3422,39 @@ See https://lists.gnu.org/r/emacs-devel/2010-07/msg01266.html +*** Building the MS-Windows port with native compilation fails + +This is known to happen when using MinGW64 GCC 13.1, and seems to +affect byte-compilation: the built Emacs crashes while byte-compiling +some Lisp files. (This doesn't happen when building a release +tarball, because all the Lisp files are already byte-compiled there, +but then Emacs could crash later when you use it to byte-compile your +or third-party Lisp packages.) + +The reason seems to be specific to MS-Windows or the MinGW64 port of +GCC 13.1, and is somehow related to optimizations in this GCC version. +There are several known workarounds: + + . Use non-default optimization flags. For example, configuring the + build like this will avoid the problem: + + CFLAGS='-O1 -gdwarf-4 -g3' ./configure ... + + (replace the ellipsis "..." with the rest of 'configure' options + and arguments). + + . Prevent GCC from performing a specific optimization: + + CFLAGS='-O2 -gdwarf-4 -g3 -fno-optimize-sibling-calls' ./configure ... + + This is actually a variant of the previous workaround, except that + it allows you to have almost the full set of optimizations used by + -O2. + + . Downgrade to GCC 12.x. + + . Build Emacs without native compilation. + *** Building the native MS-Windows port fails due to unresolved externals The linker error messages look like this: -- 2.39.5