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authorDenys Vlasenko2017-07-28 15:28:33 +0200
committerDenys Vlasenko2017-07-28 15:28:33 +0200
commit619d9b5e6848a72350126ea9c1e413fd133181e3 (patch)
tree1fe4ab734bd3b917ec4e9ef35d2c1e700a850605 /include/platform.h
parent46f3f16b587ce781ab43a7b17698e1e565b2acf7 (diff)
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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 <vda.linux@googlemail.com>
Diffstat (limited to 'include/platform.h')
-rw-r--r--include/platform.h7
1 files changed, 7 insertions, 0 deletions
diff --git a/include/platform.h b/include/platform.h
index 8210e5c..ea49c7e 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