[PATCH 09/25] snprintf: specify safe fallthrough on switches

[Luis Chamberlain <mcgrof@kernel.org>]

gcc -Wall will complain when we fallthrough on a switch
but don't mean it. Fortunately we can follow the Linux kernel
strategy to use -Wimplicit-fallthrough=2 and allow comments
to supress this to clarify this was intended.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
 Makefile.in | 4 +++-
 snprintf.c  | 3 +++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/Makefile.in b/Makefile.in
index da2fc96..ef414a5 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -16,6 +16,8 @@ DESTDIR=/
 CC=@CC@
 CFLAGS=@CFLAGS@ -I. -DVERSION=\"$(VERSION)\" -DDATADIR=\"$(datadir)\"
 CFLAGS+=`pkg-config --cflags libtirpc`
+# Allows comments to be used for fallthrough
+CFLAGS+=-Wimplicit-fallthrough=2
 CFLAGS_RPCGEN=-Wno-unused-variable
 LIBS+=`pkg-config --libs libtirpc`
 EXEEXT=@EXEEXT@
@@ -28,7 +30,7 @@ SRV_OBJS = util.o tbench_srv.o socklib.o
 all: dbench doc
 
 dbench: $(DB_OBJS)
-	$(CC) -o $@ $(DB_OBJS) $(LIBS)
+	$(CC) $(CFLAGS) -o $@ $(DB_OBJS) $(LIBS)
 
 tbench_srv: $(SRV_OBJS)
 	$(CC) -o $@ $(SRV_OBJS) $(LIBS)
diff --git a/snprintf.c b/snprintf.c
index adfd3c4..9cfc20e 100644
--- a/snprintf.c
+++ b/snprintf.c
@@ -317,6 +317,7 @@ static size_t dopr(char *buffer, size_t maxlen, const char *format, va_list args
 				break;
 			case 'X':
 				flags |= DP_F_UP;
+				/* fallthrough */
 			case 'x':
 				flags |= DP_F_UNSIGNED;
 				if (cflags == DP_C_SHORT)
@@ -339,6 +340,7 @@ static size_t dopr(char *buffer, size_t maxlen, const char *format, va_list args
 				break;
 			case 'E':
 				flags |= DP_F_UP;
+				/* fallthrough */
 			case 'e':
 				if (cflags == DP_C_LDOUBLE)
 					fvalue = va_arg (args, LDOUBLE);
@@ -348,6 +350,7 @@ static size_t dopr(char *buffer, size_t maxlen, const char *format, va_list args
 				break;
 			case 'G':
 				flags |= DP_F_UP;
+				/* fallthrough */
 			case 'g':
 				if (cflags == DP_C_LDOUBLE)
 					fvalue = va_arg (args, LDOUBLE);
-- 
2.34.1