Silence clang compiler warning: unannotated fall-through between switch labels

.github/workflows/build.yml

@@ -10,7 +10,7 @@ permissions:
   contents: read
 
 env:
-  CFLAGS_GCC_STYLE: '-Wall -Wextra -pedantic -Wdeclaration-after-statement -Wshadow -Wno-overlength-strings'
+  CFLAGS_GCC_STYLE: '-Wall -Wextra -pedantic -Wdeclaration-after-statement -Wshadow -Wno-overlength-strings -Wimplicit-fallthrough'
   CFLAGS_MSVC: '/W3'
   CFLAGS_SOLARIS_CC: '-errtags=yes -erroff=E_STATEMENT_NOT_REACHED'
   CMAKE_FLAGS: '-Wdev -Werror=dev -Wdeprecated -Werror=deprecated --warn-uninitialized'

.github/workflows/dev.yml

@@ -10,7 +10,7 @@ permissions:
   contents: read
 
 env:
-  CFLAGS_GCC_STYLE: '-Wall -Wextra -pedantic -Wdeclaration-after-statement -Wshadow -Wno-overlength-strings'
+  CFLAGS_GCC_STYLE: '-Wall -Wextra -pedantic -Wdeclaration-after-statement -Wshadow -Wno-overlength-strings -Wimplicit-fallthrough'
   CFLAGS_MSVC: '/W3'
   CMAKE_FLAGS: '-Wdev -Werror=dev -Wdeprecated -Werror=deprecated --warn-uninitialized'
 

src/pcre2_auto_possess.c

@@ -804,21 +804,21 @@ for(;;)
 
       case OP_NOT_DIGIT:
       invert_bits = TRUE;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
       case OP_DIGIT:
       set2 = (const uint8_t *)(cb->cbits + cbit_digit);
       break;
 
       case OP_NOT_WHITESPACE:
       invert_bits = TRUE;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
       case OP_WHITESPACE:
       set2 = (const uint8_t *)(cb->cbits + cbit_space);
       break;
 
       case OP_NOT_WORDCHAR:
       invert_bits = TRUE;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
       case OP_WORDCHAR:
       set2 = (const uint8_t *)(cb->cbits + cbit_word);
       break;
@@ -1101,7 +1101,7 @@ for(;;)
 
       case OP_NCLASS:
       if (chr > 255) return FALSE;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
 
       case OP_CLASS:
       if (chr > 255) break;

src/pcre2_compile.c

@@ -1936,7 +1936,7 @@ else
 
     if (c >= CHAR_8) break;
 
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     /* \0 always starts an octal number, but we may drop through to here with a
     larger first octal digit. The original code used just to take the least
@@ -2908,21 +2908,21 @@ switch(escape)
   {
   case ESC_D:
   prop = ESC_P;
-  /* Fall through */
+  PCRE2_FALLTHROUGH; /* Fall through */
   case ESC_d:
   ascii_option = PCRE2_EXTRA_ASCII_BSD;
   break;
 
   case ESC_S:
   prop = ESC_P;
-  /* Fall through */
+  PCRE2_FALLTHROUGH; /* Fall through */
   case ESC_s:
   ascii_option = PCRE2_EXTRA_ASCII_BSS;
   break;
 
   case ESC_W:
   prop = ESC_P;
-  /* Fall through */
+  PCRE2_FALLTHROUGH; /* Fall through */
   case ESC_w:
   ascii_option = PCRE2_EXTRA_ASCII_BSW;
   break;
@@ -4560,7 +4560,7 @@ while (ptr < ptrend)
 
           default:
           PCRE2_DEBUG_UNREACHABLE();
-          /* Fall through */
+          PCRE2_FALLTHROUGH; /* Fall through */
 
           case ESC_A:
           case ESC_Z:
@@ -5224,7 +5224,7 @@ while (ptr < ptrend)
         ++ptr;
         goto FAILED_FORWARD;
         }
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
 
       case CHAR_0: case CHAR_1: case CHAR_2: case CHAR_3: case CHAR_4:
       case CHAR_5: case CHAR_6: case CHAR_7: case CHAR_8: case CHAR_9:
@@ -5974,7 +5974,7 @@ for (;;)
     case OP_UCP_WORD_BOUNDARY:
     case OP_NOT_UCP_WORD_BOUNDARY:
     if (!skipassert) return code;
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     case OP_CALLOUT:
     case OP_CREF:
@@ -6493,7 +6493,7 @@ for (;; pptr++)
     case META_PRUNE:
     case META_SKIP:
     cb->had_pruneorskip = TRUE;
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
     case META_COMMIT:
     case META_FAIL:
     *code++ = verbops[(meta - META_MARK) >> 16];
@@ -6518,7 +6518,7 @@ for (;; pptr++)
     case META_PRUNE_ARG:
     case META_SKIP_ARG:
     cb->had_pruneorskip = TRUE;
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
     case META_MARK:
     case META_COMMIT_ARG:
     VERB_ARG:
@@ -7498,7 +7498,7 @@ for (;; pptr++)
       group_return = -1;  /* Set "may match empty string" */
 
       /* Now treat as a repeated OP_BRA. */
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
 
       /* If previous was a bracket group, we may have to replicate it in
       certain cases. Note that at this point we can encounter only the "basic"
@@ -8348,7 +8348,7 @@ for (;; pptr++)
       if ((options & PCRE2_UCP) != 0 && (xoptions & PCRE2_EXTRA_ASCII_BSW) == 0)
         meta_arg = (meta_arg == ESC_B)? OP_NOT_UCP_WORD_BOUNDARY :
           OP_UCP_WORD_BOUNDARY;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
 
       case ESC_A:
       if (cb->max_lookbehind == 0) cb->max_lookbehind = 1;
@@ -9282,7 +9282,7 @@ do {
 
      case OP_EXACT:
      scode += IMM2_SIZE;
-     /* Fall through */
+     PCRE2_FALLTHROUGH; /* Fall through */
 
      case OP_CHAR:
      case OP_PLUS:
@@ -9295,7 +9295,7 @@ do {
 
      case OP_EXACTI:
      scode += IMM2_SIZE;
-     /* Fall through */
+     PCRE2_FALLTHROUGH; /* Fall through */
 
      case OP_CHARI:
      case OP_PLUSI:
@@ -9727,7 +9727,7 @@ for (;; pptr++)
     case META_BACKREF_BYNAME:
     if ((cb->external_options & PCRE2_MATCH_UNSET_BACKREF) != 0)
       goto ISNOTFIXED;
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     case META_RECURSE_BYNAME:
       {
@@ -9776,7 +9776,7 @@ for (;; pptr++)
       goto RECURSE_OR_BACKREF_LENGTH;
       }
 
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
     /* For groups >= 10 - picking up group twice does no harm. */
 
     /* A true recursion implies not fixed length, but a subroutine call may
@@ -9856,7 +9856,7 @@ for (;; pptr++)
 
     case META_CAPTURE:
     group = META_DATA(*pptr);
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     case META_ATOMIC:
     case META_NOCAPTURE:
@@ -9903,7 +9903,7 @@ for (;; pptr++)
         else itemlength = (max - 1) * lastitemlength;
       break;
       }
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     /* Any other item means this branch does not have a fixed length. */
 

src/pcre2_compile_class.c

@@ -65,7 +65,7 @@ b) none of the cases here:
 #define CLASS_END_CASES(meta) \
   default: \
   PCRE2_ASSERT((meta) <= META_END); \
-  /* Fall through */ \
+  PCRE2_FALLTHROUGH; /* Fall through */ \
   case META_CLASS: \
   case META_CLASS_NOT: \
   case META_CLASS_EMPTY: \
@@ -2169,7 +2169,7 @@ switch (meta)
     }
 
   ptr++;
-  /* Fall through */
+  PCRE2_FALLTHROUGH; /* Fall through */
 
   default:
   /* Scan forward characters, ranges, and properties.

src/pcre2_convert.c

@@ -226,7 +226,7 @@ while (plength > 0)
           posix++;
           continue;    /* With next character after :] */
           }
-        /* Fall through */
+        PCRE2_FALLTHROUGH; /* Fall through */
 
         case POSIX_CLASS_NOT_STARTED:
         if (c == CHAR_LEFT_SQUARE_BRACKET)
@@ -321,15 +321,15 @@ while (plength > 0)
 
     case CHAR_LEFT_PARENTHESIS:
     bracount++;
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     case CHAR_QUESTION_MARK:
     case CHAR_PLUS:
     case CHAR_LEFT_CURLY_BRACKET:
     case CHAR_RIGHT_CURLY_BRACKET:
     case CHAR_VERTICAL_LINE:
     if (!extended) goto ESCAPE_LITERAL;
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     case CHAR_DOT:
     case CHAR_DOLLAR_SIGN:
@@ -358,7 +358,7 @@ while (plength > 0)
       posix_state = POSIX_ANCHORED;
       goto COPY_SPECIAL;
       }
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     default:
     if (c < 255 && strchr(pcre2_escaped_literals, c) != NULL)

src/pcre2_dfa_match.c

@@ -2328,7 +2328,7 @@ for (;;)
         case 0x2029:
 #endif  /* Not EBCDIC */
         if (mb->bsr_convention == PCRE2_BSR_ANYCRLF) break;
-        /* Fall through */
+        PCRE2_FALLTHROUGH; /* Fall through */
 
         case CHAR_LF:
         ADD_NEW(state_offset + 1, 0);
@@ -2440,7 +2440,7 @@ for (;;)
       caseless = TRUE;
       codevalue -= OP_STARI - OP_STAR;
 
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
       case OP_PLUS:
       case OP_MINPLUS:
       case OP_POSPLUS:
@@ -2484,7 +2484,7 @@ for (;;)
       case OP_NOTPOSQUERYI:
       caseless = TRUE;
       codevalue -= OP_STARI - OP_STAR;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
       case OP_QUERY:
       case OP_MINQUERY:
       case OP_POSQUERY:
@@ -2525,7 +2525,7 @@ for (;;)
       case OP_NOTPOSSTARI:
       caseless = TRUE;
       codevalue -= OP_STARI - OP_STAR;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
       case OP_STAR:
       case OP_MINSTAR:
       case OP_POSSTAR:
@@ -2562,7 +2562,7 @@ for (;;)
       case OP_NOTEXACTI:
       caseless = TRUE;
       codevalue -= OP_STARI - OP_STAR;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
       case OP_EXACT:
       case OP_NOTEXACT:
       count = current_state->count;  /* Number already matched */
@@ -2597,7 +2597,7 @@ for (;;)
       case OP_NOTPOSUPTOI:
       caseless = TRUE;
       codevalue -= OP_STARI - OP_STAR;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
       case OP_UPTO:
       case OP_MINUPTO:
       case OP_POSUPTO:

src/pcre2_match.c

@@ -970,7 +970,7 @@ fprintf(stderr, "++ %2ld op=%3d %s\n", Fecode - mb->start_code, *Fecode,
       Fecode += 1 + LINK_SIZE;
       continue;
       }
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     /* OP_END itself can never be reached within a recursion because that is
     picked up when the OP_KET that always precedes OP_END is reached. */
@@ -1054,7 +1054,7 @@ fprintf(stderr, "++ %2ld op=%3d %s\n", Fecode - mb->start_code, *Fecode,
       mb->hitend = TRUE;
       if (mb->partial > 1) return PCRE2_ERROR_PARTIAL;
       }
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     /* Match any single character whatsoever. */
 
@@ -6062,7 +6062,7 @@ fprintf(stderr, "++ %2ld op=%3d %s\n", Fecode - mb->start_code, *Fecode,
                 assert_accept_frame->offset_top * sizeof(PCRE2_SIZE));
           Foffset_top = assert_accept_frame->offset_top;
 
-          /* Fall through */
+          PCRE2_FALLTHROUGH; /* Fall through */
           /* In the case of a match, the captures have already been put into
           the current frame. */
 
@@ -6360,7 +6360,7 @@ fprintf(stderr, "++ %2ld op=%3d %s\n", Fecode - mb->start_code, *Fecode,
       case OP_ASSERTBACK_NA:
       if (branch_start[1 + LINK_SIZE] == OP_VREVERSE && Feptr != P->eptr)
         RRETURN(MATCH_NOMATCH);
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
 
       case OP_ASSERT_NA:
       if (Feptr > mb->last_used_ptr) mb->last_used_ptr = Feptr;
@@ -6374,12 +6374,12 @@ fprintf(stderr, "++ %2ld op=%3d %s\n", Fecode - mb->start_code, *Fecode,
       case OP_ASSERTBACK:
       if (branch_start[1 + LINK_SIZE] == OP_VREVERSE && Feptr != P->eptr)
         RRETURN(MATCH_NOMATCH);
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
 
       case OP_ASSERT:
       if (Feptr > mb->last_used_ptr) mb->last_used_ptr = Feptr;
       Feptr = P->eptr;
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
 
       /* For an atomic group, discard internal backtracking points. We must
       also ensure that any remaining branches within the top-level of the group
@@ -6403,7 +6403,7 @@ fprintf(stderr, "++ %2ld op=%3d %s\n", Fecode - mb->start_code, *Fecode,
       case OP_ASSERTBACK_NOT:
       if (branch_start[1 + LINK_SIZE] == OP_VREVERSE && Feptr != P->eptr)
         RRETURN(MATCH_NOMATCH);
-      /* Fall through */
+      PCRE2_FALLTHROUGH; /* Fall through */
 
       case OP_ASSERT_NOT:
       RRETURN(MATCH_MATCH);
@@ -6537,7 +6537,7 @@ fprintf(stderr, "++ %2ld op=%3d %s\n", Fecode - mb->start_code, *Fecode,
     if ((mb->moptions & PCRE2_NOTEOL) != 0) RRETURN(MATCH_NOMATCH);
     if ((mb->poptions & PCRE2_DOLLAR_ENDONLY) == 0) goto ASSERT_NL_OR_EOS;
 
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
     /* Unconditional end of subject assertion (\z). */
 
     case OP_EOD:
@@ -7938,7 +7938,7 @@ for(;;)
       new_start_match = mb->verb_skip_ptr;
       break;
       }
-    /* Fall through */
+    PCRE2_FALLTHROUGH; /* Fall through */
 
     /* NOMATCH and PRUNE advance by one character. THEN at this level acts
     exactly like PRUNE. Unset ignore SKIP-with-argument. */