The arm ld.so code has
#define _BM(x) (x == 32? ~0 : ~(-(1UL << (x))))
and uses _BM(32) in several places. For some reason clang doesn't
realize that the ~(-(1UL << (x))) branch is dead and warns that we
shift a 32-bit integer by 32 bits. Arguably a bug in clang, but I
noticed that the i386 code simply uses:
#define _BM(x) (~(-(1ULL << (x))))
which makes the problem go away. I also changed the type of
reloc_target_bitmask from 'int' to 'long' to match the i386 code.
ok?
Index: libexec/ld.so/arm/rtld_machine.c
===================================================================
RCS file: /cvs/src/libexec/ld.so/arm/rtld_machine.c,v
retrieving revision 1.25
diff -u -p -r1.25 rtld_machine.c
--- libexec/ld.so/arm/rtld_machine.c 24 Jan 2017 07:48:37 -0000 1.25
+++ libexec/ld.so/arm/rtld_machine.c 14 Nov 2017 10:21:55 -0000
@@ -106,8 +106,9 @@ static int reloc_target_flags[] = {
#define RELOC_USE_ADDEND(t) ((reloc_target_flags[t] & _RF_A) != 0)
#define RELOC_TARGET_SIZE(t) ((reloc_target_flags[t] >> 8) & 0xff)
#define RELOC_VALUE_RIGHTSHIFT(t) (reloc_target_flags[t] & 0xff)
-static int reloc_target_bitmask[] = {
-#define _BM(x) (x == 32? ~0 : ~(-(1UL << (x))))
+
+static long reloc_target_bitmask[] = {
+#define _BM(x) (~(-(1ULL << (x))))
_BM(0), /* 0 NONE */
_BM(24), /* 1 PC24 */
_BM(32), /* 2 ABS32 */
