libc-config: port to DragonFlyBSD 5.9

DragonFlyBSD defines __nonnull incompatibly with glibc,
so avoid the use of __nonnull in Gnulib code.
Problem reported by Gavin Smith in:
https://lists.gnu.org/r/bug-gnulib/2021-03/msg00066.html
* lib/cdefs.h (__attribute_nonnull__): Rename from __nonnull.
All uses in Gnulib changed.  There should be no need to change
glibc code that is not shared with Gnulib.
(__nonnull): New macro, defined in terms of __attribute_nonnull__,
and which can be used in glibc code that is not shared with Gnulib.

4 files changed, 40 insertions, 24 deletions

diff --git a/ChangeLog b/ChangeLog
index cf72e260e0..a5ba8488f5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2021-03-10  Paul Eggert  <eggert@cs.ucla.edu>
+
+	libc-config: port to DragonFlyBSD 5.9
+	DragonFlyBSD defines __nonnull incompatibly with glibc,
+	so avoid the use of __nonnull in Gnulib code.
+	Problem reported by Gavin Smith in:
+	https://lists.gnu.org/r/bug-gnulib/2021-03/msg00066.html
+	* lib/cdefs.h (__attribute_nonnull__): Rename from __nonnull.
+	All uses in Gnulib changed.  There should be no need to change
+	glibc code that is not shared with Gnulib.
+	(__nonnull): New macro, defined in terms of __attribute_nonnull__,
+	and which can be used in glibc code that is not shared with Gnulib.
+
 2021-03-07  Paul Eggert  <eggert@cs.ucla.edu>
 
 	manywarnings: modernize documentation
diff --git a/lib/cdefs.h b/lib/cdefs.h
index 6f12c79da6..90f97412a9 100644
--- a/lib/cdefs.h
+++ b/lib/cdefs.h
@@ -321,15 +321,15 @@
 
 /* The nonnull function attribute marks pointer parameters that
    must not be NULL.  */
-#ifndef __nonnull
+#ifndef __attribute_nonnull__
 # if __GNUC_PREREQ (3,3) || __glibc_has_attribute (__nonnull__)
-#  define __nonnull(params) __attribute__ ((__nonnull__ params))
+#  define __attribute_nonnull__(params) __attribute__ ((__nonnull__ params))
 # else
-#  define __nonnull(params)
+#  define __attribute_nonnull__(params)
 # endif
-#elif !defined __GLIBC__
-# undef __nonnull
-# define __nonnull(params) _GL_ATTRIBUTE_NONNULL (params)
+#endif
+#ifndef __nonnull
+# define __nonnull(params) __attribute_nonnull__ (params)
 #endif
 
 /* If fortification mode, we warn about unused results of certain
diff --git a/lib/libc-config.h b/lib/libc-config.h
index fcdafcb968..f14013f7e8 100644
--- a/lib/libc-config.h
+++ b/lib/libc-config.h
@@ -33,9 +33,9 @@
 #include <config.h>
 
 /* On glibc this includes <features.h> and <sys/cdefs.h> and #defines
-   _FEATURES_H, __WORDSIZE, and __set_errno.  On FreeBSD 11 it
-   includes <sys/cdefs.h> which defines __nonnull.  Elsewhere it
-   is harmless.  */
+   _FEATURES_H, __WORDSIZE, and __set_errno.  On FreeBSD 11 and
+   DragonFlyBSD 5.9 it includes <sys/cdefs.h> which defines __nonnull.
+   Elsewhere it is harmless.  */
 #include <errno.h>
 
 /* From glibc <errno.h>.  */
diff --git a/lib/malloc/dynarray-skeleton.c b/lib/malloc/dynarray-skeleton.c
index 5b9f37bdd6..48210e3252 100644
--- a/lib/malloc/dynarray-skeleton.c
+++ b/lib/malloc/dynarray-skeleton.c
@@ -192,7 +192,7 @@ DYNARRAY_NAME (free__array__) (struct DYNARRAY_STRUCT *list)
 
 /* Initialize a dynamic array object.  This must be called before any
    use of the object.  */
-__nonnull ((1))
+__attribute_nonnull__ ((1))
 static void
 DYNARRAY_NAME (init) (struct DYNARRAY_STRUCT *list)
 {
@@ -202,7 +202,7 @@ DYNARRAY_NAME (init) (struct DYNARRAY_STRUCT *list)
 }
 
 /* Deallocate the dynamic array and its elements.  */
-__attribute_maybe_unused__ __nonnull ((1))
+__attribute_maybe_unused__ __attribute_nonnull__ ((1))
 static void
 DYNARRAY_FREE (struct DYNARRAY_STRUCT *list)
 {
@@ -213,7 +213,7 @@ DYNARRAY_FREE (struct DYNARRAY_STRUCT *list)
 }
 
 /* Return true if the dynamic array is in an error state.  */
-__nonnull ((1))
+__attribute_nonnull__ ((1))
 static inline bool
 DYNARRAY_NAME (has_failed) (const struct DYNARRAY_STRUCT *list)
 {
@@ -222,7 +222,7 @@ DYNARRAY_NAME (has_failed) (const struct DYNARRAY_STRUCT *list)
 
 /* Mark the dynamic array as failed.  All elements are deallocated as
    a side effect.  */
-__nonnull ((1))
+__attribute_nonnull__ ((1))
 static void
 DYNARRAY_NAME (mark_failed) (struct DYNARRAY_STRUCT *list)
 {
@@ -236,7 +236,7 @@ DYNARRAY_NAME (mark_failed) (struct DYNARRAY_STRUCT *list)
 
 /* Return the number of elements which have been added to the dynamic
    array.  */
-__nonnull ((1))
+__attribute_nonnull__ ((1))
 static inline size_t
 DYNARRAY_NAME (size) (const struct DYNARRAY_STRUCT *list)
 {
@@ -245,7 +245,7 @@ DYNARRAY_NAME (size) (const struct DYNARRAY_STRUCT *list)
 
 /* Return a pointer to the array element at INDEX.  Terminate the
    process if INDEX is out of bounds.  */
-__nonnull ((1))
+__attribute_nonnull__ ((1))
 static inline DYNARRAY_ELEMENT *
 DYNARRAY_NAME (at) (struct DYNARRAY_STRUCT *list, size_t index)
 {
@@ -257,7 +257,7 @@ DYNARRAY_NAME (at) (struct DYNARRAY_STRUCT *list, size_t index)
 /* Return a pointer to the first array element, if any.  For a
    zero-length array, the pointer can be NULL even though the dynamic
    array has not entered the failure state.  */
-__nonnull ((1))
+__attribute_nonnull__ ((1))
 static inline DYNARRAY_ELEMENT *
 DYNARRAY_NAME (begin) (struct DYNARRAY_STRUCT *list)
 {
@@ -267,7 +267,7 @@ DYNARRAY_NAME (begin) (struct DYNARRAY_STRUCT *list)
 /* Return a pointer one element past the last array element.  For a
    zero-length array, the pointer can be NULL even though the dynamic
    array has not entered the failure state.  */
-__nonnull ((1))
+__attribute_nonnull__ ((1))
 static inline DYNARRAY_ELEMENT *
 DYNARRAY_NAME (end) (struct DYNARRAY_STRUCT *list)
 {
@@ -294,7 +294,7 @@ DYNARRAY_NAME (add__) (struct DYNARRAY_STRUCT *list, DYNARRAY_ELEMENT item)
 /* Add ITEM at the end of the array, enlarging it by one element.
    Mark *LIST as failed if the dynamic array allocation size cannot be
    increased.  */
-__nonnull ((1))
+__attribute_nonnull__ ((1))
 static inline void
 DYNARRAY_NAME (add) (struct DYNARRAY_STRUCT *list, DYNARRAY_ELEMENT item)
 {
@@ -348,7 +348,8 @@ DYNARRAY_NAME (emplace__) (struct DYNARRAY_STRUCT *list)
 /* Allocate a place for a new element in *LIST and return a pointer to
    it.  The pointer can be NULL if the dynamic array cannot be
    enlarged due to a memory allocation failure.  */
-__attribute_maybe_unused__ __attribute_warn_unused_result__ __nonnull ((1))
+__attribute_maybe_unused__ __attribute_warn_unused_result__
+__attribute_nonnull__ ((1))
 static
 /* Avoid inlining with the larger initialization code.  */
 #if !(defined (DYNARRAY_ELEMENT_INIT) || defined (DYNARRAY_ELEMENT_FREE))
@@ -372,7 +373,7 @@ DYNARRAY_NAME (emplace) (struct DYNARRAY_STRUCT *list)
    existing size, new elements are added (which can be initialized).
    Otherwise, the list is truncated, and elements are freed.  Return
    false on memory allocation failure (and mark *LIST as failed).  */
-__attribute_maybe_unused__ __nonnull ((1))
+__attribute_maybe_unused__ __attribute_nonnull__ ((1))
 static bool
 DYNARRAY_NAME (resize) (struct DYNARRAY_STRUCT *list, size_t size)
 {
@@ -417,7 +418,7 @@ DYNARRAY_NAME (resize) (struct DYNARRAY_STRUCT *list, size_t size)
 }
 
 /* Remove the last element of LIST if it is present.  */
-__attribute_maybe_unused__ __nonnull ((1))
+__attribute_maybe_unused__ __attribute_nonnull__ ((1))
 static void
 DYNARRAY_NAME (remove_last) (struct DYNARRAY_STRUCT *list)
 {
@@ -434,7 +435,7 @@ DYNARRAY_NAME (remove_last) (struct DYNARRAY_STRUCT *list)
 
 /* Remove all elements from the list.  The elements are freed, but the
    list itself is not.  */
-__attribute_maybe_unused__ __nonnull ((1))
+__attribute_maybe_unused__ __attribute_nonnull__ ((1))
 static void
 DYNARRAY_NAME (clear) (struct DYNARRAY_STRUCT *list)
 {
@@ -452,7 +453,8 @@ DYNARRAY_NAME (clear) (struct DYNARRAY_STRUCT *list)
    stored in *RESULT if LIST refers to an empty list.  On success, the
    pointer in *RESULT is heap-allocated and must be deallocated using
    free.  */
-__attribute_maybe_unused__ __attribute_warn_unused_result__ __nonnull ((1, 2))
+__attribute_maybe_unused__ __attribute_warn_unused_result__
+__attribute_nonnull__ ((1, 2))
 static bool
 DYNARRAY_NAME (finalize) (struct DYNARRAY_STRUCT *list,
                           DYNARRAY_FINAL_TYPE *result)
@@ -483,7 +485,8 @@ DYNARRAY_NAME (finalize) (struct DYNARRAY_STRUCT *list,
    have a sentinel at the end).  If LENGTHP is not NULL, the array
    length is written to *LENGTHP.  *LIST is re-initialized and can be
    reused.  */
-__attribute_maybe_unused__ __attribute_warn_unused_result__ __nonnull ((1))
+__attribute_maybe_unused__ __attribute_warn_unused_result__
+__attribute_nonnull__ ((1))
 static DYNARRAY_ELEMENT *
 DYNARRAY_NAME (finalize) (struct DYNARRAY_STRUCT *list, size_t *lengthp)
 {