gcc/

	* common.opt (Wimplicit-fallthrough) Turn into alias to
	-Wimplicit-fallthrough=3.  Remove EnabledBy.
	(Wimplicit-fallthrough=): New option.
	* gimplify.c (warn_implicit_fallthrough_r): Use
	OPT_Wimplicit_fallthrough_ instead of OPT_Wimplicit_fallthrough.
	* doc/invoke.texi (-Wimplicit-fallthrough): Document as alias
	to -Wimplicit-fallthrough=3.
	(-Wimplicit-fallthrough=): Document.
gcc/c-family/
	* c.opt (Wextra): Add as C/C++/ObjC/ObjC++ option.
	(Wimplicit-fallthrough=): Enable for these languages by -Wextra.
	* c-opts.c (sanitize_cpp_opts): Initialize
	cpp_opts->cpp_warn_implicit_fallthrough.
gcc/testsuite/
	* c-c++-common/Wimplicit-fallthrough-25.c: New test.
	* c-c++-common/Wimplicit-fallthrough-26.c: New test.
	* c-c++-common/Wimplicit-fallthrough-27.c: New test.
	* c-c++-common/Wimplicit-fallthrough-28.c: New test.
	* c-c++-common/Wimplicit-fallthrough-29.c: New test.
	* c-c++-common/Wimplicit-fallthrough-30.c: New test.
	* c-c++-common/Wimplicit-fallthrough-31.c: New test.
	* c-c++-common/Wimplicit-fallthrough-32.c: New test.
	* c-c++-common/Wimplicit-fallthrough-33.c: New test.
libcpp/
	* include/cpplib.h (struct cpp_options): Add
	cpp_warn_implicit_fallthrough.
	* init.c (cpp_create_reader): Initialize it to 0.
	* lex.c (fallthrough_comment_p): Handle different
	cpp_warn_implicit_fallthrough levels.  Whitespace fixes.

From-SVN: r241013

17 files changed, 398 insertions, 15 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 110c2f3..6facb48 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2016-10-12  Jakub Jelinek  <jakub@redhat.com>
+
+	* common.opt (Wimplicit-fallthrough) Turn into alias to
+	-Wimplicit-fallthrough=3.  Remove EnabledBy.
+	(Wimplicit-fallthrough=): New option.
+	* gimplify.c (warn_implicit_fallthrough_r): Use
+	OPT_Wimplicit_fallthrough_ instead of OPT_Wimplicit_fallthrough.
+	* doc/invoke.texi (-Wimplicit-fallthrough): Document as alias
+	to -Wimplicit-fallthrough=3.
+	(-Wimplicit-fallthrough=): Document.
+
 2016-10-11  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* config/sparc/sparc.c (emit_scc_insn): Remove direct support for EQ
diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index 78a4947..64619fc 100644
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,10 @@
+2016-10-12  Jakub Jelinek  <jakub@redhat.com>
+
+	* c.opt (Wextra): Add as C/C++/ObjC/ObjC++ option.
+	(Wimplicit-fallthrough=): Enable for these languages by -Wextra.
+	* c-opts.c (sanitize_cpp_opts): Initialize
+	cpp_opts->cpp_warn_implicit_fallthrough.
+
 2016-10-11  Marek Polacek  <polacek@redhat.com>
 
 	* c-common.c (warning_candidate_p): Change the return type to bool
diff --git a/gcc/c-family/c-opts.c b/gcc/c-family/c-opts.c
index c5a699d..da62b55 100644
--- a/gcc/c-family/c-opts.c
+++ b/gcc/c-family/c-opts.c
@@ -1279,6 +1279,11 @@ sanitize_cpp_opts (void)
   if (flag_working_directory == -1)
     flag_working_directory = (debug_info_level != DINFO_LEVEL_NONE);
 
+  if (warn_implicit_fallthrough < 5)
+    cpp_opts->cpp_warn_implicit_fallthrough = warn_implicit_fallthrough;
+  else
+    cpp_opts->cpp_warn_implicit_fallthrough = 0;
+
   if (cpp_opts->directives_only)
     {
       if (cpp_warn_unused_macros)
diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index e146781..82c992c 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -462,6 +462,10 @@ Werror-implicit-function-declaration
 C ObjC RejectNegative Warning Alias(Werror=, implicit-function-declaration)
 This switch is deprecated; use -Werror=implicit-function-declaration instead.
 
+Wextra
+C ObjC C++ ObjC++ Warning
+; in common.opt
+
 Wfloat-conversion
 C ObjC C++ ObjC++ Var(warn_float_conversion) Warning LangEnabledBy(C ObjC C++ ObjC++,Wconversion)
 Warn for implicit type conversions that cause loss of floating point precision.
@@ -536,6 +540,10 @@ Wimplicit
 C ObjC Var(warn_implicit) Warning LangEnabledBy(C ObjC,Wall)
 Warn about implicit declarations.
 
+Wimplicit-fallthrough=
+LangEnabledBy(C ObjC C++ ObjC++,Wextra,3,0)
+; in common.opt
+
 Wdouble-promotion
 C ObjC C++ ObjC++ Var(warn_double_promotion) Warning
 Warn about implicit conversions from \"float\" to \"double\".
diff --git a/gcc/common.opt b/gcc/common.opt
index 3425c19..15679c5 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -602,7 +602,10 @@ Common Var(warn_hsa) Init(1) Warning
 Warn when a function cannot be expanded to HSAIL.
 
 Wimplicit-fallthrough
-Common Var(warn_implicit_fallthrough) Warning EnabledBy(Wextra)
+Common Alias(Wimplicit-fallthrough=,3,0) Warning
+
+Wimplicit-fallthrough=
+Common Var(warn_implicit_fallthrough) RejectNegative Joined UInteger Warning
 Warn when a switch case falls through.
 
 Winline
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index fa693ba..c11f1d5 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -273,8 +273,8 @@ Objective-C and Objective-C++ Dialects}.
 -Wformat-security  -Wformat-signedness  -Wformat-y2k -Wframe-address @gol
 -Wframe-larger-than=@var{len} -Wno-free-nonheap-object -Wjump-misses-init @gol
 -Wignored-qualifiers  -Wignored-attributes  -Wincompatible-pointer-types @gol
--Wimplicit  -Wimplicit-fallthrough  -Wimplicit-function-declaration @gol
--Wimplicit-int @gol
+-Wimplicit  -Wimplicit-fallthrough  -Wimplicit-fallthrough=@var{n} @gol
+-Wimplicit-function-declaration  -Wimplicit-int @gol
 -Winit-self  -Winline  -Wno-int-conversion  -Wint-in-bool-context @gol
 -Wno-int-to-pointer-cast -Winvalid-memory-model -Wno-invalid-offsetof @gol
 -Winvalid-pch -Wlarger-than=@var{len} @gol
@@ -3734,7 +3734,7 @@ name is still supported, but the newer name is more descriptive.)
 @gccoptlist{-Wclobbered  @gol
 -Wempty-body  @gol
 -Wignored-qualifiers @gol
--Wimplicit-fallthrough @gol
+-Wimplicit-fallthrough=3 @gol
 -Wmissing-field-initializers  @gol
 -Wmissing-parameter-type @r{(C only)}  @gol
 -Wold-style-declaration @r{(C only)}  @gol
@@ -4106,6 +4106,12 @@ This warning is enabled by @option{-Wall}.
 @item -Wimplicit-fallthrough
 @opindex Wimplicit-fallthrough
 @opindex Wno-implicit-fallthrough
+@option{-Wimplicit-fallthrough} is the same as @option{-Wimplicit-fallthrough=3}
+and @option{-Wno-implicit-fallthrough} is the same as
+@option{-Wimplicit-fallthrough=0}.
+
+@item -Wimplicit-fallthrough=@var{n}
+@opindex Wimplicit-fallthrough=
 Warn when a switch case falls through.  For example:
 
 @smallexample
@@ -4126,7 +4132,7 @@ switch (cond)
 
 This warning does not warn when the last statement of a case cannot
 fall through, e.g. when there is a return statement or a call to function
-declared with the noreturn attribute.  @option{-Wimplicit-fallthrough}
+declared with the noreturn attribute.  @option{-Wimplicit-fallthrough=}
 also takes into account control flow statements, such as ifs, and only
 warns when appropriate.  E.g.@:
 
@@ -4169,9 +4175,23 @@ switch (cond)
 C++17 provides a standard way to suppress the @option{-Wimplicit-fallthrough}
 warning using @code{[[fallthrough]];} instead of the GNU attribute.  In C++11
 or C++14 users can use @code{[[gnu::fallthrough]];}, which is a GNU extension.
-Instead of the these attributes, it is also possible to add a "falls through"
+Instead of the these attributes, it is also possible to add a fallthrough
 comment to silence the warning.  The whole body of the C or C++ style comment
-should match one of the following regular expressions:
+should match the given regular expressions listed below.  The option argument
+@var{n} specifies what kind of comments are accepted:
+
+@itemize @bullet
+
+@item @option{-Wimplicit-fallthrough=0} disables the warning altogether.
+
+@item @option{-Wimplicit-fallthrough=1} matches @code{.*} regular
+expression, any comment is used as fallthrough comment.
+
+@item @option{-Wimplicit-fallthrough=2} case insensitively matches
+@code{.*falls?[ \t-]*thr(ough|u).*} regular expression.
+
+@item @option{-Wimplicit-fallthrough=3} case sensitively matches one of the
+following regular expressions:
 
 @itemize @bullet
 
@@ -4179,17 +4199,37 @@ should match one of the following regular expressions:
 
 @item @code{@@fallthrough@@}
 
-@item @code{lint -fallthrough ?}
+@item @code{lint -fallthrough[ \t]*}
+
+@item @code{[ \t.!]*(ELSE,? |INTENTIONAL(LY)? )?@*FALL(S | |-)?THR(OUGH|U)[ \t.!]*(-[^\n\r]*)?}
+
+@item @code{[ \t.!]*(Else,? |Intentional(ly)? )?@*Fall((s | |-)[Tt]|t)hr(ough|u)[ \t.!]*(-[^\n\r]*)?}
 
-@item @code{[ \t.!]*(ELSE,? |INTENTIONAL(LY)? )?FALL(S | |-)?THR(OUGH|U)[ \t.!]*(-[^\n\r]*)?}
+@item @code{[ \t.!]*([Ee]lse,? |[Ii]ntentional(ly)? )?@*fall(s | |-)?thr(ough|u)[ \t.!]*(-[^\n\r]*)?}
+
+@end itemize
 
-@item @code{[ \t.!]*(Else,? |Intentional(ly)? )?Fall((s | |-)[Tt]|t)hr(ough|u)[ \t.!]*(-[^\n\r]*)?}
+@item @option{-Wimplicit-fallthrough=4} case sensitively matches one of the
+following regular expressions:
+
+@itemize @bullet
+
+@item @code{-fallthrough}
+
+@item @code{@@fallthrough@@}
+
+@item @code{lint -fallthrough[ \t]*}
+
+@item @code{[ \t]*FALLTHR(OUGH|U)[ \t]*}
+
+@end itemize
 
-@item @code{[ \t.!]*([Ee]lse,? |[Ii]ntentional(ly)? )?fall(s | |-)?thr(ough|u)[ \t.!]*(-[^\n\r]*)?}
+@item @option{-Wimplicit-fallthrough=5} doesn't recognize any comments as
+fallthrough comments, only attributes disable the warning.
 
 @end itemize
 
-and the comment needs to be followed after optional whitespace and other comments
+The comment needs to be followed after optional whitespace and other comments
 by @code{case} or @code{default} keywords or by a user label that preceeds some
 @code{case} or @code{default} label.
 
@@ -4206,7 +4246,7 @@ switch (cond)
 @end group
 @end smallexample
 
-This warning is enabled by @option{-Wextra}.
+The @option{-Wimplicit-fallthrough=3} warning is enabled by @option{-Wextra}.
 
 @item -Wignored-qualifiers @r{(C and C++ only)}
 @opindex Wignored-qualifiers
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index 0b1a0be..2f074f9 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -1918,7 +1918,7 @@ warn_implicit_fallthrough_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
 	    else if (gimple_code (prev) == GIMPLE_LABEL
 		     && (label = gimple_label_label (as_a <glabel *> (prev)))
 		     && (l = find_label_entry (&labels, label)))
-	      warned_p = warning_at (l->loc, OPT_Wimplicit_fallthrough,
+	      warned_p = warning_at (l->loc, OPT_Wimplicit_fallthrough_,
 				     "this statement may fall through");
 	    else if (!gimple_call_internal_p (prev, IFN_FALLTHROUGH)
 		     /* Try to be clever and don't warn when the statement
@@ -1926,7 +1926,7 @@ warn_implicit_fallthrough_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
 		     && gimple_stmt_may_fallthru (prev)
 		     && gimple_has_location (prev))
 	      warned_p = warning_at (gimple_location (prev),
-				     OPT_Wimplicit_fallthrough,
+				     OPT_Wimplicit_fallthrough_,
 				     "this statement may fall through");
 	    if (warned_p)
 	      inform (gimple_location (next), "here");
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index c0f20cd..4423684 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,15 @@
+2016-10-12  Jakub Jelinek  <jakub@redhat.com>
+
+	* c-c++-common/Wimplicit-fallthrough-25.c: New test.
+	* c-c++-common/Wimplicit-fallthrough-26.c: New test.
+	* c-c++-common/Wimplicit-fallthrough-27.c: New test.
+	* c-c++-common/Wimplicit-fallthrough-28.c: New test.
+	* c-c++-common/Wimplicit-fallthrough-29.c: New test.
+	* c-c++-common/Wimplicit-fallthrough-30.c: New test.
+	* c-c++-common/Wimplicit-fallthrough-31.c: New test.
+	* c-c++-common/Wimplicit-fallthrough-32.c: New test.
+	* c-c++-common/Wimplicit-fallthrough-33.c: New test.
+
 2016-10-11  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gcc.target/sparc/setcc-4.c: Adjust.
diff --git a/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-25.c b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-25.c
new file mode 100644
index 0000000..f622878
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-25.c
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Wextra" } */
+
+void bar (int);
+
+void
+foo (int i)
+{
+  switch (i)
+    {
+    case 1:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (1);
+    case 2:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (2);
+      /* Some comment.  */
+    case 3:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (3);
+      /* Here we really do want to fALl   tHRoUgh and we mean it!  */
+    case 4:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (4);
+      /* Intentionally fall through.  */
+    case 5:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (5);
+      /* FALLTHROUGH */
+    case 6:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (6);
+      __attribute__((fallthrough));
+    case 7:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (7);
+    default:
+      break;
+    }
+}
diff --git a/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-26.c b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-26.c
new file mode 100644
index 0000000..3c62de1
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-26.c
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Wimplicit-fallthrough" } */
+
+void bar (int);
+
+void
+foo (int i)
+{
+  switch (i)
+    {
+    case 1:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (1);
+    case 2:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (2);
+      /* Some comment.  */
+    case 3:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (3);
+      /* Here we really do want to fALl   tHRoUgh and we mean it!  */
+    case 4:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (4);
+      /* Intentionally fall through.  */
+    case 5:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (5);
+      /* FALLTHROUGH */
+    case 6:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (6);
+      __attribute__((fallthrough));
+    case 7:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (7);
+    default:
+      break;
+    }
+}
diff --git a/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-27.c b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-27.c
new file mode 100644
index 0000000..7ea0815
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-27.c
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Wimplicit-fallthrough=1" } */
+
+void bar (int);
+
+void
+foo (int i)
+{
+  switch (i)
+    {
+    case 1:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (1);
+    case 2:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (2);
+      /* Some comment.  */
+    case 3:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (3);
+      /* Here we really do want to fALl   tHRoUgh and we mean it!  */
+    case 4:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (4);
+      /* Intentionally fall through.  */
+    case 5:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (5);
+      /* FALLTHROUGH */
+    case 6:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (6);
+      __attribute__((fallthrough));
+    case 7:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (7);
+    default:
+      break;
+    }
+}
diff --git a/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-28.c b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-28.c
new file mode 100644
index 0000000..7c685f6
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-28.c
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Wimplicit-fallthrough=2" } */
+
+void bar (int);
+
+void
+foo (int i)
+{
+  switch (i)
+    {
+    case 1:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (1);
+    case 2:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (2);
+      /* Some comment.  */
+    case 3:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (3);
+      /* Here we really do want to fALl   tHRoUgh and we mean it!  */
+    case 4:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (4);
+      /* Intentionally fall through.  */
+    case 5:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (5);
+      /* FALLTHROUGH */
+    case 6:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (6);
+      __attribute__((fallthrough));
+    case 7:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (7);
+    default:
+      break;
+    }
+}
diff --git a/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-29.c b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-29.c
new file mode 100644
index 0000000..9863e9d
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-29.c
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Wimplicit-fallthrough=3" } */
+
+void bar (int);
+
+void
+foo (int i)
+{
+  switch (i)
+    {
+    case 1:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (1);
+    case 2:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (2);
+      /* Some comment.  */
+    case 3:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (3);
+      /* Here we really do want to fALl   tHRoUgh and we mean it!  */
+    case 4:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (4);
+      /* Intentionally fall through.  */
+    case 5:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (5);
+      /* FALLTHROUGH */
+    case 6:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (6);
+      __attribute__((fallthrough));
+    case 7:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (7);
+    default:
+      break;
+    }
+}
diff --git a/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-30.c b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-30.c
new file mode 100644
index 0000000..54d22df
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-30.c
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Wimplicit-fallthrough=4" } */
+
+void bar (int);
+
+void
+foo (int i)
+{
+  switch (i)
+    {
+    case 1:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (1);
+    case 2:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (2);
+      /* Some comment.  */
+    case 3:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (3);
+      /* Here we really do want to fALl   tHRoUgh and we mean it!  */
+    case 4:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (4);
+      /* Intentionally fall through.  */
+    case 5:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (5);
+      /* FALLTHROUGH */
+    case 6:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (6);
+      __attribute__((fallthrough));
+    case 7:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (7);
+    default:
+      break;
+    }
+}
diff --git a/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-31.c b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-31.c
new file mode 100644
index 0000000..de20d92
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-31.c
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Wimplicit-fallthrough=5" } */
+
+void bar (int);
+
+void
+foo (int i)
+{
+  switch (i)
+    {
+    case 1:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (1);
+    case 2:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (2);
+      /* Some comment.  */
+    case 3:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (3);
+      /* Here we really do want to fALl   tHRoUgh and we mean it!  */
+    case 4:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (4);
+      /* Intentionally fall through.  */
+    case 5:			/* { dg-warning "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (5);
+      /* FALLTHROUGH */
+    case 6:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (6);
+      __attribute__((fallthrough));
+    case 7:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (7);
+    default:
+      break;
+    }
+}
diff --git a/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-32.c b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-32.c
new file mode 100644
index 0000000..cd0b8ce
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-32.c
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Wimplicit-fallthrough=0" } */
+
+void bar (int);
+
+void
+foo (int i)
+{
+  switch (i)
+    {
+    case 1:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (1);
+    case 2:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (2);
+      /* Some comment.  */
+    case 3:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (3);
+      /* Here we really do want to fALl   tHRoUgh and we mean it!  */
+    case 4:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (4);
+      /* Intentionally fall through.  */
+    case 5:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (5);
+      /* FALLTHROUGH */
+    case 6:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (6);
+      __attribute__((fallthrough));
+    case 7:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (7);
+    default:
+      break;
+    }
+}
diff --git a/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-33.c b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-33.c
new file mode 100644
index 0000000..336cc44
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Wimplicit-fallthrough-33.c
@@ -0,0 +1,33 @@
+/* { dg-do compile } */
+/* { dg-options "-Wno-implicit-fallthrough" } */
+
+void bar (int);
+
+void
+foo (int i)
+{
+  switch (i)
+    {
+    case 1:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (1);
+    case 2:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (2);
+      /* Some comment.  */
+    case 3:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (3);
+      /* Here we really do want to fALl   tHRoUgh and we mean it!  */
+    case 4:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (4);
+      /* Intentionally fall through.  */
+    case 5:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (5);
+      /* FALLTHROUGH */
+    case 6:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (6);
+      __attribute__((fallthrough));
+    case 7:			/* { dg-bogus "this statement may \[fla\]* through" "" { target *-*-* } .+1 } */
+      bar (7);
+    default:
+      break;
+    }
+}