From 11169e6f1a9104182176c67623f7f9579aa96997 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Thu, 13 Jun 2013 10:04:08 -0700 Subject: [PATCH] * DEBUG: Document -Og. --- etc/ChangeLog | 4 ++++ etc/DEBUG | 7 ++++--- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/etc/ChangeLog b/etc/ChangeLog index f80c1b6973c..e7fdc25be51 100644 --- a/etc/ChangeLog +++ b/etc/ChangeLog @@ -1,3 +1,7 @@ +2013-06-13 Paul Eggert + + * DEBUG: Document -Og. + 2013-06-05 Teodor Zlatanov * NEWS: Document new prog-mode symbol prettify support. diff --git a/etc/DEBUG b/etc/DEBUG index 709e8987d03..a76a60641c9 100644 --- a/etc/DEBUG +++ b/etc/DEBUG @@ -24,8 +24,10 @@ There are several ways to overcome that difficulty, they are all described in the node "Auto-loading safe path" in the GDB user manual. ** When you are trying to analyze failed assertions or backtraces, it -will be essential to compile Emacs either completely without -optimizations (set CFLAGS to "-O0 -g3") or at least (when using GCC) +is essential to compile Emacs with flags suitable for debugging. +With GCC 4.8 or later, you can invoke 'make' with CFLAGS="-Og -g3". +With older GCC or non-GCC commpilers, you can use CFLAGS="-O0 -g3". +With GCC and higher optimization levels such as -O2, at least compile with the -fno-crossjumping option in CFLAGS. Failure to do so may make the compiler recycle the same abort call for all assertions in a given function, rendering the stack backtrace useless for identifying @@ -769,4 +771,3 @@ Local variables: mode: outline paragraph-separate: "[ ]*$" end: - -- 2.11.4.GIT