diff options
Diffstat (limited to 'etc/DEBUG')
| -rw-r--r-- | etc/DEBUG | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/etc/DEBUG b/etc/DEBUG index 709e8987d03..b2a943f5d71 100644 --- a/etc/DEBUG +++ b/etc/DEBUG @@ -24,12 +24,14 @@ 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) -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 -the specific failed assertion. +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 compilers, you can use CFLAGS="-O0 -g3". +With GCC and higher optimization levels such as -O2, the +-fno-omit-frame-pointer and -fno-crossjumping options are often +essential. The latter prevents GCC from using the same abort call for +all assertions in a given function, rendering the stack backtrace +useless for identifying the specific failed assertion. ** It is a good idea to run Emacs under GDB (or some other suitable debugger) *all the time*. Then, when Emacs crashes, you will be able @@ -769,4 +771,3 @@ Local variables: mode: outline paragraph-separate: "[ ]*$" end: - |