Fix remaining static analysis warnings

Fix or suppress the remaining warnings generated by static analysis.
This is a necessary step before we can incorporate static analysis into
CI. Where possible, I've preferred to modify the code itself instead of
just disabling the warning with a magic comment, so that if we decide to
use different static analysis tools in the future we will be covered
against them raising similar warnings.

include/jemalloc/internal/jemalloc_internal_inlines_c.h

@@ -325,6 +325,8 @@ imalloc_fastpath(size_t size, void *(fallback_alloc)(size_t)) {
 	tcache_t *tcache = tsd_tcachep_get(tsd);
 	assert(tcache == tcache_get(tsd));
 	cache_bin_t *bin = &tcache->bins[ind];
+	/* Suppress spurious warning from static analysis */
+	assert(bin != NULL);
 	bool tcache_success;
 	void *ret;
 

include/jemalloc/internal/ph.h

@@ -127,6 +127,7 @@ phn_merge_ordered(void *phn0, void *phn1, size_t offset,
 	phn0child = phn_lchild_get(phn0, offset);
 	phn_next_set(phn1, phn0child, offset);
 	if (phn0child != NULL) {
+		/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
 		phn_prev_set(phn0child, phn1, offset);
 	}
 	phn_lchild_set(phn0, phn1, offset);
@@ -143,6 +144,7 @@ phn_merge(void *phn0, void *phn1, size_t offset, ph_cmp_t cmp) {
 		phn_merge_ordered(phn0, phn1, offset, cmp);
 		result = phn0;
 	} else {
+		/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
 		phn_merge_ordered(phn1, phn0, offset, cmp);
 		result = phn1;
 	}
@@ -188,10 +190,12 @@ phn_merge_siblings(void *phn, size_t offset, ph_cmp_t cmp) {
 				phn_prev_set(phn1, NULL, offset);
 				phn_next_set(phn1, NULL, offset);
 				phn0 = phn_merge(phn0, phn1, offset, cmp);
+				/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
 				phn_next_set(tail, phn0, offset);
 				tail = phn0;
 				phn0 = phnrest;
 			} else {
+				/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
 				phn_next_set(tail, phn0, offset);
 				tail = phn0;
 				phn0 = NULL;
@@ -210,6 +214,7 @@ phn_merge_siblings(void *phn, size_t offset, ph_cmp_t cmp) {
 				if (head == NULL) {
 					break;
 				}
+				/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
 				phn_next_set(tail, phn0, offset);
 				tail = phn0;
 				phn0 = head;
@@ -298,6 +303,7 @@ ph_try_aux_merge_pair(ph_t *ph, size_t offset, ph_cmp_t cmp) {
 	phn0 = phn_merge(phn0, phn1, offset, cmp);
 	phn_next_set(phn0, next_phn1, offset);
 	if (next_phn1 != NULL) {
+		/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
 		phn_prev_set(next_phn1, phn0, offset);
 	}
 	phn_next_set(ph->root, phn0, offset);

include/jemalloc/internal/rb.h

@@ -867,6 +867,7 @@ a_prefix##remove(a_rbt_type *rbtree, a_type *node) {			\
 	}								\
     }									\
     rb_remove_safety_checks(nodep, __func__);				\
+    assert(nodep != NULL);                                              \
     assert(nodep->node == node);					\
     pathp--;								\
     if (pathp->node != node) {						\

include/jemalloc/internal/rtree.h

@@ -268,6 +268,10 @@ rtree_contents_encode(rtree_contents_t contents, void **bits,
     unsigned *additional) {
 #ifdef RTREE_LEAF_COMPACT
 	*bits = (void *)rtree_leaf_elm_bits_encode(contents);
+	/* Suppress spurious warning from static analysis */
+	if (config_debug) {
+		*additional = 0;
+	}
 #else
 	*additional = (unsigned)contents.metadata.slab
 	    | ((unsigned)contents.metadata.is_head << 1)
@@ -299,7 +303,6 @@ rtree_leaf_elm_write(tsdn_t *tsdn, rtree_t *rtree,
 	assert((uintptr_t)contents.edata % EDATA_ALIGNMENT == 0);
 	void *bits;
 	unsigned additional;
-
 	rtree_contents_encode(contents, &bits, &additional);
 	rtree_leaf_elm_write_commit(tsdn, rtree, elm, bits, additional);
 }

include/jemalloc/internal/witness.h

@@ -341,6 +341,9 @@ witness_lock(witness_tsdn_t *witness_tsdn, witness_t *witness) {
 		witness_lock_error(witnesses, witness);
 	}
 
+	/* Suppress spurious warning from static analysis */
+	assert(ql_empty(witnesses) ||
+	    qr_prev(ql_first(witnesses), link) != NULL);
 	ql_elm_new(witness, link);
 	ql_tail_insert(witnesses, witness, link);
 }