Add a comment describing why it's important for the values in this

file to be correct, and how to generate them automatically.

Caused much pain and suffering for:	peter

6 files changed, 42 insertions, 0 deletions

diff --git a/lib/libc/alpha/arith.h b/lib/libc/alpha/arith.h
index de6c33d..c8af6de 100644
--- a/lib/libc/alpha/arith.h
+++ b/lib/libc/alpha/arith.h
@@ -4,6 +4,13 @@
  * $FreeBSD$
  */
 
+/*
+ * NOTE: The definitions in this file must be correct or strtod(3) and
+ * floating point formats in printf(3) will break!  The file can be
+ * generated by running contrib/gdtoa/arithchk.c on the target
+ * architecture.  See contrib/gdtoa/gdtoaimp.h for details.
+ */
+
 #define IEEE_8087
 #define Arith_Kind_ASL 1
 #define Long int
diff --git a/lib/libc/amd64/arith.h b/lib/libc/amd64/arith.h
index 202264d..ecb1a33 100644
--- a/lib/libc/amd64/arith.h
+++ b/lib/libc/amd64/arith.h
@@ -4,6 +4,13 @@
  * $FreeBSD$
  */
 
+/*
+ * NOTE: The definitions in this file must be correct or strtod(3) and
+ * floating point formats in printf(3) will break!  The file can be
+ * generated by running contrib/gdtoa/arithchk.c on the target
+ * architecture.  See contrib/gdtoa/gdtoaimp.h for details.
+ */
+
 #define IEEE_8087
 #define Arith_Kind_ASL 1
 #define Long int
diff --git a/lib/libc/i386/arith.h b/lib/libc/i386/arith.h
index d1bcfb6..2d65061 100644
--- a/lib/libc/i386/arith.h
+++ b/lib/libc/i386/arith.h
@@ -4,5 +4,12 @@
  * $FreeBSD$
  */
 
+/*
+ * NOTE: The definitions in this file must be correct or strtod(3) and
+ * floating point formats in printf(3) will break!  The file can be
+ * generated by running contrib/gdtoa/arithchk.c on the target
+ * architecture.  See contrib/gdtoa/gdtoaimp.h for details.
+ */
+
 #define IEEE_8087
 #define Arith_Kind_ASL 1
diff --git a/lib/libc/ia64/arith.h b/lib/libc/ia64/arith.h
index 9102826..6726528 100644
--- a/lib/libc/ia64/arith.h
+++ b/lib/libc/ia64/arith.h
@@ -4,6 +4,13 @@
  * $FreeBSD$
  */
 
+/*
+ * NOTE: The definitions in this file must be correct or strtod(3) and
+ * floating point formats in printf(3) will break!  The file can be
+ * generated by running contrib/gdtoa/arithchk.c on the target
+ * architecture.  See contrib/gdtoa/gdtoaimp.h for details.
+ */
+
 #include <machine/endian.h>
 
 #if _BYTE_ORDER == _LITTLE_ENDIAN
diff --git a/lib/libc/powerpc/arith.h b/lib/libc/powerpc/arith.h
index 9f4cfe4..8e2c9ec 100644
--- a/lib/libc/powerpc/arith.h
+++ b/lib/libc/powerpc/arith.h
@@ -4,6 +4,13 @@
  * $FreeBSD$
  */
 
+/*
+ * NOTE: The definitions in this file must be correct or strtod(3) and
+ * floating point formats in printf(3) will break!  The file can be
+ * generated by running contrib/gdtoa/arithchk.c on the target
+ * architecture.  See contrib/gdtoa/gdtoaimp.h for details.
+ */
+
 #define IEEE_MC68k
 #define Arith_Kind_ASL 2
 #define Double_Align
diff --git a/lib/libc/sparc64/arith.h b/lib/libc/sparc64/arith.h
index c954a9c..3c35b80 100644
--- a/lib/libc/sparc64/arith.h
+++ b/lib/libc/sparc64/arith.h
@@ -4,6 +4,13 @@
  * $FreeBSD$
  */
 
+/*
+ * NOTE: The definitions in this file must be correct or strtod(3) and
+ * floating point formats in printf(3) will break!  The file can be
+ * generated by running contrib/gdtoa/arithchk.c on the target
+ * architecture.  See contrib/gdtoa/gdtoaimp.h for details.
+ */
+
 #define IEEE_MC68k
 #define Arith_Kind_ASL 2
 #define Long int