Push the floating-point test into a separate file.

Hopefully, that will make sure we don't optimize away anything that
will, for example, cause us not to do things differently on 32-bit x86
using the x87 instructions.

Author: guyharris

CMakeLists.txt

@@ -1110,7 +1110,7 @@ if(NOT C_ADDITIONAL_FLAGS STREQUAL "")
     set_target_properties(netdissect PROPERTIES COMPILE_FLAGS ${C_ADDITIONAL_FLAGS})
 endif()
 
-set(TCPDUMP_SOURCE_LIST_C tcpdump.c)
+set(TCPDUMP_SOURCE_LIST_C fptype.c tcpdump.c)
 
 if(NOT HAVE_BPF_DUMP)
     set(TCPDUMP_SOURCE_LIST_C ${TCPDUMP_SOURCE_LIST_C} bpf_dump.c)

Makefile.in

@@ -70,7 +70,7 @@ DEPENDENCY_CFLAG = @DEPENDENCY_CFLAG@
 	@rm -f $@
 	$(CC) $(FULL_CFLAGS) -c $(srcdir)/$*.c
 
-CSRC =	tcpdump.c
+CSRC =	fptype.c tcpdump.c
 
 LIBNETDISSECT_SRC=\
 	addrtoname.c \

fptype.c

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 1982, 1986, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+
+#include "netdissect-stdinc.h"
+
+#include "fptype.h"
+
+void
+float_type_check(uint32_t in)
+{
+	union { /* int to float conversion buffer */
+		float f;
+		uint32_t i;
+	} f;
+
+	f.i = in;
+	printf("%.3f\n", f.f*8/1000000);
+}

fptype.h

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 1982, 1986, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+extern void float_type_check(uint32_t);

tcpdump.c

@@ -150,6 +150,8 @@ The Regents of the University of California.  All rights reserved.\n";
 
 #include "print.h"
 
+#include "fptype.h"
+
 #ifndef PATH_MAX
 #define PATH_MAX 1024
 #endif
@@ -1901,14 +1903,7 @@ main(int argc, char **argv)
 			 * may differ (e.g., it might be 32-bit, 64-bit,
 			 * or 80-bit).
 			 */
-			{
-				union { /* int to float conversion buffer */
-					float f;
-					uint32_t i;
-				} f;
-				f.i = 0x4e93312d;
-				printf("%.3f\n", f.f*8/1000000);
-			}
+			float_type_check(0x4e93312d);
 			return 0;
 
 		default: