Commit 42597aa3 authored by Eduard Zingerman's avatar Eduard Zingerman Committed by Andrii Nakryiko
Browse files

libbpf: Hashmap.h update to fix build issues using LLVM14 

A fix for the LLVM compilation error while building bpftool.
Replaces the expression:

  _Static_assert((p) == NULL || ...)

by expression:

  _Static_assert((__builtin_constant_p((p)) ? (p) == NULL : 0) || ...)

When "p" is not a constant the former is not considered to be a
constant expression by LLVM 14.

The error was introduced in the following patch-set: [1].
The error was reported here: [2].

  [1] https://lore.kernel.org/bpf/20221109142611.879983-1-eddyz87@gmail.com/
  [2] https://lore.kernel.org/all/202211110355.BcGcbZxP-lkp@intel.com/



Reported-by: default avatarkernel test robot <lkp@intel.com>
Fixes: c302378b ("libbpf: Hashmap interface update to allow both long and void* keys/values")
Signed-off-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Acked-by: default avatarStanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221110223240.1350810-1-eddyz87@gmail.com
parent c7028aa2

tools/lib/bpf/hashmap.h

+2 −1
Original line number Diff line number Diff line
@@ -123,7 +123,8 @@ enum hashmap_insert_strategy { 
};



#define hashmap_cast_ptr(p) ({								\

	_Static_assert((p) == NULL || sizeof(*(p)) == sizeof(long),			\

	_Static_assert((__builtin_constant_p((p)) ? (p) == NULL : 0) ||			\

				sizeof(*(p)) == sizeof(long),				\

		       #p " pointee should be a long-sized integer or a pointer");	\

	(long *)(p);									\

})

tools/perf/util/hashmap.h

+2 −1
Original line number Diff line number Diff line
@@ -123,7 +123,8 @@ enum hashmap_insert_strategy { 
};



#define hashmap_cast_ptr(p) ({								\

	_Static_assert((p) == NULL || sizeof(*(p)) == sizeof(long),			\

	_Static_assert((__builtin_constant_p((p)) ? (p) == NULL : 0) ||			\

				sizeof(*(p)) == sizeof(long),				\

		       #p " pointee should be a long-sized integer or a pointer");	\

	(long *)(p);									\

})