From 619d9b5e6848a72350126ea9c1e413fd133181e3 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 28 Jul 2017 15:28:33 +0200 Subject: ash: less hackish implementation of evaltreenr() Defining a function alias with __attribute__ ((alias("evaltree"),__noreturn__)) is not that usual, and clang had a bug which made it misunderstand this construct. Switch to: ALWAYS_INLINE NORETURN evaltreenr() { evaltree(); unreachable(); } Older gcc's do not know unreachable(), on them we pay the price of having a few extra calls to abort(): function old new delta evalsubshell 151 156 +5 evalpipe 357 362 +5 argstr 1141 1144 +3 On newer gcc, code size does not change. Signed-off-by: Denys Vlasenko --- include/platform.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/platform.h') diff --git a/include/platform.h b/include/platform.h index 8210e5c49..ea49c7e92 100644 --- a/include/platform.h +++ b/include/platform.h @@ -45,6 +45,13 @@ #define UNUSED_PARAM __attribute__ ((__unused__)) #define NORETURN __attribute__ ((__noreturn__)) + +#if __GNUC_PREREQ(4,5) +# define bb_unreachable(altcode) __builtin_unreachable() +#else +# define bb_unreachable(altcode) altcode +#endif + /* "The malloc attribute is used to tell the compiler that a function * may be treated as if any non-NULL pointer it returns cannot alias * any other pointer valid when the function returns. This will often -- cgit v1.2.3