Merge tag 'fallthrough-fixes-clang-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull fallthrough fixes from Gustavo A. R. Silva:
 "Fix many fall-through warnings when building with Clang 12.0.0
  using -Wimplicit-fallthrough.

   - powerpc: boot: include compiler_attributes.h (Nick Desaulniers)

   - Revert "lib: Revert use of fallthrough pseudo-keyword in lib/"
     (Nick Desaulniers)

   - powerpc: fix -Wimplicit-fallthrough (Nick Desaulniers)

   - lib: Fix fall-through warnings for Clang (Gustavo A. R. Silva)"

* tag 'fallthrough-fixes-clang-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  lib: Fix fall-through warnings for Clang
  powerpc: fix -Wimplicit-fallthrough
  Revert "lib: Revert use of fallthrough pseudo-keyword in lib/"
  powerpc: boot: include compiler_attributes.h

24 files changed, 86 insertions, 78 deletions

diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index f8ce6d2dde7b..1659963a8f1d 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -31,6 +31,7 @@ endif
 BOOTCFLAGS    := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
 		 -fno-strict-aliasing -O2 -msoft-float -mno-altivec -mno-vsx \
 		 -pipe -fomit-frame-pointer -fno-builtin -fPIC -nostdinc \
+		 -include $(srctree)/include/linux/compiler_attributes.h \
 		 $(LINUXINCLUDE)
 
 ifdef CONFIG_PPC64_BOOT_WRAPPER
diff --git a/arch/powerpc/boot/decompress.c b/arch/powerpc/boot/decompress.c
index 8bf39ef7d2df..6098b879ac97 100644
--- a/arch/powerpc/boot/decompress.c
+++ b/arch/powerpc/boot/decompress.c
@@ -21,7 +21,6 @@
 
 #define STATIC static
 #define INIT
-#define __always_inline inline
 
 /*
  * The build process will copy the required zlib source files and headers
diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index 38ae5933d917..e9d4eb6144e1 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -355,6 +355,7 @@ static int __init prom_strtobool(const char *s, bool *res)
 		default:
 			break;
 		}
+		break;
 	default:
 		break;
 	}
diff --git a/arch/powerpc/kernel/uprobes.c b/arch/powerpc/kernel/uprobes.c
index d200e7df7167..e8a63713e655 100644
--- a/arch/powerpc/kernel/uprobes.c
+++ b/arch/powerpc/kernel/uprobes.c
@@ -141,6 +141,7 @@ int arch_uprobe_exception_notify(struct notifier_block *self,
 	case DIE_SSTEP:
 		if (uprobe_post_sstep_notifier(regs))
 			return NOTIFY_STOP;
+		break;
 	default:
 		break;
 	}
diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
index 7b25548ec42b..e106909ff9c3 100644
--- a/arch/powerpc/perf/imc-pmu.c
+++ b/arch/powerpc/perf/imc-pmu.c
@@ -1500,6 +1500,7 @@ static int update_pmu_ops(struct imc_pmu *pmu)
 		pmu->pmu.stop = trace_imc_event_stop;
 		pmu->pmu.read = trace_imc_event_read;
 		pmu->attr_groups[IMC_FORMAT_ATTR] = &trace_imc_format_group;
+		break;
 	default:
 		break;
 	}
diff --git a/lib/asn1_decoder.c b/lib/asn1_decoder.c
index 58f72b25f8e9..13da529e2e72 100644
--- a/lib/asn1_decoder.c
+++ b/lib/asn1_decoder.c
@@ -381,7 +381,7 @@ next_op:
 	case ASN1_OP_END_SET_ACT:
 		if (unlikely(!(flags & FLAG_MATCHED)))
 			goto tag_mismatch;
-		/* fall through */
+		fallthrough;
 
 	case ASN1_OP_END_SEQ:
 	case ASN1_OP_END_SET_OF:
@@ -448,7 +448,7 @@ next_op:
 			pc += asn1_op_lengths[op];
 			goto next_op;
 		}
-		/* fall through */
+		fallthrough;
 
 	case ASN1_OP_ACT:
 		ret = actions[machine[pc + 1]](context, hdr, tag, data + tdp, len);
diff --git a/lib/assoc_array.c b/lib/assoc_array.c
index 6f4bcf524554..04c98799c3ba 100644
--- a/lib/assoc_array.c
+++ b/lib/assoc_array.c
@@ -1113,7 +1113,7 @@ struct assoc_array_edit *assoc_array_delete(struct assoc_array *array,
 						index_key))
 				goto found_leaf;
 		}
-		/* fall through */
+		fallthrough;
 	case assoc_array_walk_tree_empty:
 	case assoc_array_walk_found_wrong_shortcut:
 	default:
diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 649ed44f199c..9f8c70a98fcf 100644
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -827,7 +827,7 @@ int __init xbc_init(char *buf, const char **emsg, int *epos)
 							q - 2);
 				break;
 			}
-			/* fall through */
+			fallthrough;
 		case '=':
 			ret = xbc_parse_kv(&p, q, c);
 			break;
@@ -836,7 +836,7 @@ int __init xbc_init(char *buf, const char **emsg, int *epos)
 			break;
 		case '#':
 			q = skip_comment(q);
-			/* fall through */
+			fallthrough;
 		case ';':
 		case '\n':
 			ret = xbc_parse_key(&p, q);
diff --git a/lib/cmdline.c b/lib/cmdline.c
index 9e186234edc0..b390dd03363b 100644
--- a/lib/cmdline.c
+++ b/lib/cmdline.c
@@ -144,27 +144,28 @@ unsigned long long memparse(const char *ptr, char **retptr)
 	case 'E':
 	case 'e':
 		ret <<= 10;
-		/* fall through */
+		fallthrough;
 	case 'P':
 	case 'p':
 		ret <<= 10;
-		/* fall through */
+		fallthrough;
 	case 'T':
 	case 't':
 		ret <<= 10;
-		/* fall through */
+		fallthrough;
 	case 'G':
 	case 'g':
 		ret <<= 10;
-		/* fall through */
+		fallthrough;
 	case 'M':
 	case 'm':
 		ret <<= 10;
-		/* fall through */
+		fallthrough;
 	case 'K':
 	case 'k':
 		ret <<= 10;
 		endptr++;
+		fallthrough;
 	default:
 		break;
 	}
diff --git a/lib/dim/net_dim.c b/lib/dim/net_dim.c
index a4db51c21266..06811d866775 100644
--- a/lib/dim/net_dim.c
+++ b/lib/dim/net_dim.c
@@ -233,7 +233,7 @@ void net_dim(struct dim *dim, struct dim_sample end_sample)
 			schedule_work(&dim->work);
 			break;
 		}
-		/* fall through */
+		fallthrough;
 	case DIM_START_MEASURE:
 		dim_update_sample(end_sample.event_ctr, end_sample.pkt_ctr,
 				  end_sample.byte_ctr, &dim->start_sample);
diff --git a/lib/dim/rdma_dim.c b/lib/dim/rdma_dim.c
index f7e26c7b4749..15462d54758d 100644
--- a/lib/dim/rdma_dim.c
+++ b/lib/dim/rdma_dim.c
@@ -59,7 +59,7 @@ static bool rdma_dim_decision(struct dim_stats *curr_stats, struct dim *dim)
 			break;
 		case DIM_STATS_WORSE:
 			dim_turn(dim);
-			/* fall through */
+			fallthrough;
 		case DIM_STATS_BETTER:
 			step_res = rdma_dim_step(dim);
 			if (step_res == DIM_ON_EDGE)
@@ -94,7 +94,7 @@ void rdma_dim(struct dim *dim, u64 completions)
 			schedule_work(&dim->work);
 			break;
 		}
-		/* fall through */
+		fallthrough;
 	case DIM_START_MEASURE:
 		dim->state = DIM_MEASURE_IN_PROGRESS;
 		dim_update_sample_with_comps(curr_sample->event_ctr, 0, 0,
diff --git a/lib/glob.c b/lib/glob.c
index 52e3ed7e4a9b..85ecbda45cd8 100644
--- a/lib/glob.c
+++ b/lib/glob.c
@@ -102,7 +102,7 @@ bool __pure glob_match(char const *pat, char const *str)
 			break;
 		case '\\':
 			d = *pat++;
-			/* fall through */
+			fallthrough;
 		default:	/* Literal character */
 literal:
 			if (c == d) {
diff --git a/lib/kstrtox.c b/lib/kstrtox.c
index a14ccf905055..a118b0b1e9b2 100644
--- a/lib/kstrtox.c
+++ b/lib/kstrtox.c
@@ -355,6 +355,7 @@ int kstrtobool(const char *s, bool *res)
 		default:
 			break;
 		}
+		break;
 	default:
 		break;
 	}
diff --git a/lib/nlattr.c b/lib/nlattr.c
index 09aa181569e0..5b6116e81f9f 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -432,7 +432,7 @@ static int validate_nla(const struct nlattr *nla, int maxtype,
 			err = -EINVAL;
 			goto out_err;
 		}
-		/* fall through */
+		fallthrough;
 
 	case NLA_STRING:
 		if (attrlen < 1)
diff --git a/lib/siphash.c b/lib/siphash.c
index c47bb6ff2149..a90112ee72a1 100644
--- a/lib/siphash.c
+++ b/lib/siphash.c
@@ -68,11 +68,11 @@ u64 __siphash_aligned(const void *data, size_t len, const siphash_key_t *key)
 						  bytemask_from_count(left)));
 #else
 	switch (left) {
-	case 7: b |= ((u64)end[6]) << 48; /* fall through */
-	case 6: b |= ((u64)end[5]) << 40; /* fall through */
-	case 5: b |= ((u64)end[4]) << 32; /* fall through */
+	case 7: b |= ((u64)end[6]) << 48; fallthrough;
+	case 6: b |= ((u64)end[5]) << 40; fallthrough;
+	case 5: b |= ((u64)end[4]) << 32; fallthrough;
 	case 4: b |= le32_to_cpup(data); break;
-	case 3: b |= ((u64)end[2]) << 16; /* fall through */
+	case 3: b |= ((u64)end[2]) << 16; fallthrough;
 	case 2: b |= le16_to_cpup(data); break;
 	case 1: b |= end[0];
 	}
@@ -101,11 +101,11 @@ u64 __siphash_unaligned(const void *data, size_t len, const siphash_key_t *key)
 						  bytemask_from_count(left)));
 #else
 	switch (left) {
-	case 7: b |= ((u64)end[6]) << 48; /* fall through */
-	case 6: b |= ((u64)end[5]) << 40; /* fall through */
-	case 5: b |= ((u64)end[4]) << 32; /* fall through */
+	case 7: b |= ((u64)end[6]) << 48; fallthrough;
+	case 6: b |= ((u64)end[5]) << 40; fallthrough;
+	case 5: b |= ((u64)end[4]) << 32; fallthrough;
 	case 4: b |= get_unaligned_le32(end); break;
-	case 3: b |= ((u64)end[2]) << 16; /* fall through */
+	case 3: b |= ((u64)end[2]) << 16; fallthrough;
 	case 2: b |= get_unaligned_le16(end); break;
 	case 1: b |= end[0];
 	}
@@ -268,11 +268,11 @@ u32 __hsiphash_aligned(const void *data, size_t len, const hsiphash_key_t *key)
 						  bytemask_from_count(left)));
 #else
 	switch (left) {
-	case 7: b |= ((u64)end[6]) << 48; /* fall through */
-	case 6: b |= ((u64)end[5]) << 40; /* fall through */
-	case 5: b |= ((u64)end[4]) << 32; /* fall through */
+	case 7: b |= ((u64)end[6]) << 48; fallthrough;
+	case 6: b |= ((u64)end[5]) << 40; fallthrough;
+	case 5: b |= ((u64)end[4]) << 32; fallthrough;
 	case 4: b |= le32_to_cpup(data); break;
-	case 3: b |= ((u64)end[2]) << 16; /* fall through */
+	case 3: b |= ((u64)end[2]) << 16; fallthrough;
 	case 2: b |= le16_to_cpup(data); break;
 	case 1: b |= end[0];
 	}
@@ -301,11 +301,11 @@ u32 __hsiphash_unaligned(const void *data, size_t len,
 						  bytemask_from_count(left)));
 #else
 	switch (left) {
-	case 7: b |= ((u64)end[6]) << 48; /* fall through */
-	case 6: b |= ((u64)end[5]) << 40; /* fall through */
-	case 5: b |= ((u64)end[4]) << 32; /* fall through */
+	case 7: b |= ((u64)end[6]) << 48; fallthrough;
+	case 6: b |= ((u64)end[5]) << 40; fallthrough;
+	case 5: b |= ((u64)end[4]) << 32; fallthrough;
 	case 4: b |= get_unaligned_le32(end); break;
-	case 3: b |= ((u64)end[2]) << 16; /* fall through */
+	case 3: b |= ((u64)end[2]) << 16; fallthrough;
 	case 2: b |= get_unaligned_le16(end); break;
 	case 1: b |= end[0];
 	}
@@ -431,7 +431,7 @@ u32 __hsiphash_aligned(const void *data, size_t len, const hsiphash_key_t *key)
 		v0 ^= m;
 	}
 	switch (left) {
-	case 3: b |= ((u32)end[2]) << 16; /* fall through */
+	case 3: b |= ((u32)end[2]) << 16; fallthrough;
 	case 2: b |= le16_to_cpup(data); break;
 	case 1: b |= end[0];
 	}
@@ -454,7 +454,7 @@ u32 __hsiphash_unaligned(const void *data, size_t len,
 		v0 ^= m;
 	}
 	switch (left) {
-	case 3: b |= ((u32)end[2]) << 16; /* fall through */
+	case 3: b |= ((u32)end[2]) << 16; fallthrough;
 	case 2: b |= get_unaligned_le16(end); break;
 	case 1: b |= end[0];
 	}
diff --git a/lib/ts_fsm.c b/lib/ts_fsm.c
index ab749ec10ab5..64fd9015ad80 100644
--- a/lib/ts_fsm.c
+++ b/lib/ts_fsm.c
@@ -193,7 +193,7 @@ startover:
 				TOKEN_MISMATCH();
 
 			block_idx++;
-			/* fall through */
+			fallthrough;
 
 		case TS_FSM_ANY:
 			if (next == NULL)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 14c9a6af1b23..3b53c73580c5 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1265,7 +1265,7 @@ char *mac_address_string(char *buf, char *end, u8 *addr,
 
 	case 'R':
 		reversed = true;
-		/* fall through */
+		fallthrough;
 
 	default:
 		separator = ':';
@@ -1682,7 +1682,7 @@ char *uuid_string(char *buf, char *end, const u8 *addr,
 	switch (*(++fmt)) {
 	case 'L':
 		uc = true;
-		/* fall through */
+		fallthrough;
 	case 'l':
 		index = guid_index;
 		break;
@@ -2219,7 +2219,7 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 	case 'S':
 	case 's':
 		ptr = dereference_symbol_descriptor(ptr);
-		/* fall through */
+		fallthrough;
 	case 'B':
 		return symbol_string(buf, end, ptr, spec, fmt);
 	case 'R':
@@ -2450,7 +2450,7 @@ qualifier:
 
 	case 'x':
 		spec->flags |= SMALL;
-		/* fall through */
+		fallthrough;
 
 	case 'X':
 		spec->base = 16;
@@ -2459,6 +2459,7 @@ qualifier:
 	case 'd':
 	case 'i':
 		spec->flags |= SIGN;
+		break;
 	case 'u':
 		break;
 
@@ -2468,7 +2469,7 @@ qualifier:
 		 * utility, treat it as any other invalid or
 		 * unsupported format specifier.
 		 */
-		/* fall through */
+		fallthrough;
 
 	default:
 		WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
@@ -3411,10 +3412,10 @@ int vsscanf(const char *buf, const char *fmt, va_list args)
 			break;
 		case 'i':
 			base = 0;
-			/* fall through */
+			fallthrough;
 		case 'd':
 			is_sign = true;
-			/* fall through */
+			fallthrough;
 		case 'u':
 			break;
 		case '%':
diff --git a/lib/xz/xz_dec_lzma2.c b/lib/xz/xz_dec_lzma2.c
index 65a1aad8c223..ca2603abee08 100644
--- a/lib/xz/xz_dec_lzma2.c
+++ b/lib/xz/xz_dec_lzma2.c
@@ -1043,7 +1043,7 @@ XZ_EXTERN enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s,
 
 			s->lzma2.sequence = SEQ_LZMA_PREPARE;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_LZMA_PREPARE:
 			if (s->lzma2.compressed < RC_INIT_BYTES)
@@ -1055,7 +1055,7 @@ XZ_EXTERN enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s,
 			s->lzma2.compressed -= RC_INIT_BYTES;
 			s->lzma2.sequence = SEQ_LZMA_RUN;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_LZMA_RUN:
 			/*
diff --git a/lib/xz/xz_dec_stream.c b/lib/xz/xz_dec_stream.c
index 32ab2a08b7cb..fea86deaaa01 100644
--- a/lib/xz/xz_dec_stream.c
+++ b/lib/xz/xz_dec_stream.c
@@ -583,7 +583,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
 			if (ret != XZ_OK)
 				return ret;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_BLOCK_START:
 			/* We need one byte of input to continue. */
@@ -608,7 +608,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
 			s->temp.pos = 0;
 			s->sequence = SEQ_BLOCK_HEADER;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_BLOCK_HEADER:
 			if (!fill_temp(s, b))
@@ -620,7 +620,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
 
 			s->sequence = SEQ_BLOCK_UNCOMPRESS;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_BLOCK_UNCOMPRESS:
 			ret = dec_block(s, b);
@@ -629,7 +629,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
 
 			s->sequence = SEQ_BLOCK_PADDING;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_BLOCK_PADDING:
 			/*
@@ -651,7 +651,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
 
 			s->sequence = SEQ_BLOCK_CHECK;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_BLOCK_CHECK:
 			if (s->check_type == XZ_CHECK_CRC32) {
@@ -675,7 +675,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
 
 			s->sequence = SEQ_INDEX_PADDING;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_INDEX_PADDING:
 			while ((s->index.size + (b->in_pos - s->in_start))
@@ -699,7 +699,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
 
 			s->sequence = SEQ_INDEX_CRC32;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_INDEX_CRC32:
 			ret = crc32_validate(s, b);
@@ -709,7 +709,7 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
 			s->temp.size = STREAM_HEADER_SIZE;
 			s->sequence = SEQ_STREAM_FOOTER;
 
-			/* fall through */
+			fallthrough;
 
 		case SEQ_STREAM_FOOTER:
 			if (!fill_temp(s, b))
diff --git a/lib/zlib_inflate/inflate.c b/lib/zlib_inflate/inflate.c
index 67cc9b08ae9d..ee39b5eb71f7 100644
--- a/lib/zlib_inflate/inflate.c
+++ b/lib/zlib_inflate/inflate.c
@@ -396,7 +396,7 @@ int zlib_inflate(z_streamp strm, int flush)
             strm->adler = state->check = REVERSE(hold);
             INITBITS();
             state->mode = DICT;
-	    /* fall through */
+	    fallthrough;
         case DICT:
             if (state->havedict == 0) {
                 RESTORE();
@@ -404,10 +404,10 @@ int zlib_inflate(z_streamp strm, int flush)
             }
             strm->adler = state->check = zlib_adler32(0L, NULL, 0);
             state->mode = TYPE;
-	    /* fall through */
+	    fallthrough;
         case TYPE:
             if (flush == Z_BLOCK) goto inf_leave;
-	    /* fall through */
+	    fallthrough;
         case TYPEDO:
             INFLATE_TYPEDO_HOOK(strm, flush);
             if (state->last) {
@@ -446,7 +446,7 @@ int zlib_inflate(z_streamp strm, int flush)
             state->length = (unsigned)hold & 0xffff;
             INITBITS();
             state->mode = COPY;
-	    /* fall through */
+	    fallthrough;
         case COPY:
             copy = state->length;
             if (copy) {
@@ -480,7 +480,7 @@ int zlib_inflate(z_streamp strm, int flush)
 #endif
             state->have = 0;
             state->mode = LENLENS;
-	    /* fall through */
+	    fallthrough;
         case LENLENS:
             while (state->have < state->ncode) {
                 NEEDBITS(3);
@@ -501,7 +501,7 @@ int zlib_inflate(z_streamp strm, int flush)
             }
             state->have = 0;
             state->mode = CODELENS;
-	    /* fall through */
+	    fallthrough;
         case CODELENS:
             while (state->have < state->nlen + state->ndist) {
                 for (;;) {
@@ -575,7 +575,7 @@ int zlib_inflate(z_streamp strm, int flush)
                 break;
             }
             state->mode = LEN;
-	    /* fall through */
+	    fallthrough;
         case LEN:
             if (have >= 6 && left >= 258) {
                 RESTORE();
@@ -615,7 +615,7 @@ int zlib_inflate(z_streamp strm, int flush)
             }
             state->extra = (unsigned)(this.op) & 15;
             state->mode = LENEXT;
-	    /* fall through */
+	    fallthrough;
         case LENEXT:
             if (state->extra) {
                 NEEDBITS(state->extra);
@@ -623,7 +623,7 @@ int zlib_inflate(z_streamp strm, int flush)
                 DROPBITS(state->extra);
             }
             state->mode = DIST;
-	    /* fall through */
+	    fallthrough;
         case DIST:
             for (;;) {
                 this = state->distcode[BITS(state->distbits)];
@@ -649,7 +649,7 @@ int zlib_inflate(z_streamp strm, int flush)
             state->offset = (unsigned)this.val;
             state->extra = (unsigned)(this.op) & 15;
             state->mode = DISTEXT;
-	    /* fall through */
+	    fallthrough;
         case DISTEXT:
             if (state->extra) {
                 NEEDBITS(state->extra);
@@ -669,7 +669,7 @@ int zlib_inflate(z_streamp strm, int flush)
                 break;
             }
             state->mode = MATCH;
-	    /* fall through */
+	    fallthrough;
         case MATCH:
             if (left == 0) goto inf_leave;
             copy = out - left;
@@ -720,7 +720,7 @@ int zlib_inflate(z_streamp strm, int flush)
                 INITBITS();
             }
             state->mode = DONE;
-	    /* fall through */
+	    fallthrough;
         case DONE:
             ret = Z_STREAM_END;
             goto inf_leave;
diff --git a/lib/zstd/bitstream.h b/lib/zstd/bitstream.h
index 3a49784d5c61..5d6343c1a909 100644
--- a/lib/zstd/bitstream.h
+++ b/lib/zstd/bitstream.h
@@ -259,16 +259,17 @@ ZSTD_STATIC size_t BIT_initDStream(BIT_DStream_t *bitD, const void *srcBuffer, s
 		bitD->bitContainer = *(const BYTE *)(bitD->start);
 		switch (srcSize) {
 		case 7: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[6]) << (sizeof(bitD->bitContainer) * 8 - 16);
-			/* fall through */
+			fallthrough;
 		case 6: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[5]) << (sizeof(bitD->bitContainer) * 8 - 24);
-			/* fall through */
+			fallthrough;
 		case 5: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[4]) << (sizeof(bitD->bitContainer) * 8 - 32);
-			/* fall through */
+			fallthrough;
 		case 4: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[3]) << 24;
-			/* fall through */
+			fallthrough;
 		case 3: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[2]) << 16;
-			/* fall through */
+			fallthrough;
 		case 2: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[1]) << 8;
+			fallthrough;
 		default:;
 		}
 		{
diff --git a/lib/zstd/compress.c b/lib/zstd/compress.c
index 5e0b67003e55..b080264ed3ad 100644
--- a/lib/zstd/compress.c
+++ b/lib/zstd/compress.c
@@ -3182,7 +3182,7 @@ static size_t ZSTD_compressStream_generic(ZSTD_CStream *zcs, void *dst, size_t *
 				zcs->outBuffFlushedSize = 0;
 				zcs->stage = zcss_flush; /* pass-through to flush stage */
 			}
-			/* fall through */
+			fallthrough;
 
 		case zcss_flush: {
 			size_t const toFlush = zcs->outBuffContentSize - zcs->outBuffFlushedSize;
diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c
index db6761ea4deb..66cd487a326a 100644
--- a/lib/zstd/decompress.c
+++ b/lib/zstd/decompress.c
@@ -442,7 +442,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx *dctx, const void *src, size_t srcSize
 		case set_repeat:
 			if (dctx->litEntropy == 0)
 				return ERROR(dictionary_corrupted);
-			/* fall through */
+			fallthrough;
 		case set_compressed:
 			if (srcSize < 5)
 				return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for case 3 */
@@ -1768,7 +1768,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, c
 			return 0;
 		}
 		dctx->expected = 0; /* not necessary to copy more */
-		/* fall through */
+		fallthrough;
 
 	case ZSTDds_decodeFrameHeader:
 		memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected);
@@ -2309,7 +2309,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, ZSTD_inB
 		switch (zds->stage) {
 		case zdss_init:
 			ZSTD_resetDStream(zds); /* transparent reset on starting decoding a new frame */
-			/* fall through */
+			fallthrough;
 
 		case zdss_loadHeader: {
 			size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize);
@@ -2376,7 +2376,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, ZSTD_inB
 			}
 			zds->stage = zdss_read;
 		}
-			/* fall through */
+			fallthrough;
 
 		case zdss_read: {
 			size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
@@ -2405,7 +2405,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, ZSTD_inB
 			zds->stage = zdss_load;
 			/* pass-through */
 		}
-			/* fall through */
+			fallthrough;
 
 		case zdss_load: {
 			size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx);
@@ -2438,7 +2438,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, ZSTD_inB
 				/* pass-through */
 			}
 		}
-			/* fall through */
+			fallthrough;
 
 		case zdss_flush: {
 			size_t const toFlushSize = zds->outEnd - zds->outStart;
diff --git a/lib/zstd/huf_compress.c b/lib/zstd/huf_compress.c
index e727812d12aa..fd32838c185f 100644
--- a/lib/zstd/huf_compress.c
+++ b/lib/zstd/huf_compress.c
@@ -556,10 +556,11 @@ size_t HUF_compress1X_usingCTable(void *dst, size_t dstSize, const void *src, si
 	n = srcSize & ~3; /* join to mod 4 */
 	switch (srcSize & 3) {
 	case 3: HUF_encodeSymbol(&bitC, ip[n + 2], CTable); HUF_FLUSHBITS_2(&bitC);
-		/* fall through */
+		fallthrough;
 	case 2: HUF_encodeSymbol(&bitC, ip[n + 1], CTable); HUF_FLUSHBITS_1(&bitC);
-		/* fall through */
+		fallthrough;
 	case 1: HUF_encodeSymbol(&bitC, ip[n + 0], CTable); HUF_FLUSHBITS(&bitC);
+		fallthrough;
 	case 0:
 	default:;
 	}