Merge branch 'jk/clang-pedantic' into maint

A few unportable C construct have been spotted by clang compiler
and have been fixed.

* jk/clang-pedantic:
  bswap: add NO_UNALIGNED_LOADS define
  avoid shifting signed integers 31 bits

builtin/receive-pack.c

@@ -1618,7 +1618,7 @@ static void prepare_shallow_update(struct command *commands,
 				continue;
 			si->need_reachability_test[i]++;
 			for (k = 0; k < 32; k++)
-				if (si->used_shallow[i][j] & (1 << k))
+				if (si->used_shallow[i][j] & (1U << k))
 					si->shallow_ref[j * 32 + k]++;
 		}
 

cache.h

@@ -214,7 +214,7 @@ struct cache_entry {
 #define CE_INTENT_TO_ADD     (1 << 29)
 #define CE_SKIP_WORKTREE     (1 << 30)
 /* CE_EXTENDED2 is for future extension */
-#define CE_EXTENDED2         (1 << 31)
+#define CE_EXTENDED2         (1U << 31)
 
 #define CE_EXTENDED_FLAGS (CE_INTENT_TO_ADD | CE_SKIP_WORKTREE)
 

compat/bswap.h

@@ -149,11 +149,12 @@ static inline uint64_t git_bswap64(uint64_t x)
  * and is faster on architectures with memory alignment issues.
  */
 
-#if defined(__i386__) || defined(__x86_64__) || \
+#if !defined(NO_UNALIGNED_LOADS) && ( \
+    defined(__i386__) || defined(__x86_64__) || \
     defined(_M_IX86) || defined(_M_X64) || \
     defined(__ppc__) || defined(__ppc64__) || \
     defined(__powerpc__) || defined(__powerpc64__) || \
-    defined(__s390__) || defined(__s390x__)
+    defined(__s390__) || defined(__s390x__))
 
 #define get_be16(p)	ntohs(*(unsigned short *)(p))
 #define get_be32(p)	ntohl(*(unsigned int *)(p))

diff.h

@@ -91,7 +91,7 @@ typedef struct strbuf *(*diff_prefix_fn_t)(struct diff_options *opt, void *data)
 #define DIFF_OPT_DIRSTAT_BY_LINE     (1 << 28)
 #define DIFF_OPT_FUNCCONTEXT         (1 << 29)
 #define DIFF_OPT_PICKAXE_IGNORE_CASE (1 << 30)
-#define DIFF_OPT_DEFAULT_FOLLOW_RENAMES (1 << 31)
+#define DIFF_OPT_DEFAULT_FOLLOW_RENAMES (1U << 31)
 
 #define DIFF_OPT_TST(opts, flag)    ((opts)->flags & DIFF_OPT_##flag)
 #define DIFF_OPT_TOUCHED(opts, flag)    ((opts)->touched_flags & DIFF_OPT_##flag)