[groff] 67/115: [build]: Improve portability to unfree compilers.

[G. Branden Robinson]

gbranden pushed a commit to branch branden-2022-06-01
in repository groff.

commit 4f89d7ef1fd3f94e422d635bcb06f4112bc269b7
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Sun Apr 16 00:30:29 2023 -0500

    [build]: Improve portability to unfree compilers.
    
    * bootstrap.conf (gnulib_modules): Add "attribute".
    * src/libs/libgroff/getopt.c:
    * src/libs/libgroff/new.cpp: Include gnulib's "attribute.h" header file.
    * src/libs/libgroff/getopt.c (_getopt_initialize):
    * src/libs/libgroff/new.cpp (operator delete): Replace GNU C unused
      attribute syntax with gnulib's "MAYBE_UNUSED".
    
    Thanks to Bruno Haible for the report and suggested remedy.
    
    ANNOUNCE: Drop item about builds failing with MSVC due to GNU C-style
    attribute usage.  This might no longer happen, but there could be other
    reasons we don't successfully build with it.
---
 ANNOUNCE                   |  4 ----
 ChangeLog                  | 14 ++++++++++++++
 bootstrap.conf             |  1 +
 src/libs/libgroff/getopt.c |  5 +++--
 src/libs/libgroff/new.cpp  |  5 +++--
 5 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/ANNOUNCE b/ANNOUNCE
index c43285ed4..aed8600e8 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -164,10 +164,6 @@ o Solaris 10 has known problems with automated tests; see 
the "PROBLEMS"
 o There is a problem building on "newlib"-using systems when X11 support
   is enabled; see the "PROBLEMS" file in the distribution archive.
 
-o The build is known to not work with the MSVC compiler.  There are no
-  plans to address this before C23 standardized attributes become
-  available.
-
 News
 ====
 
diff --git a/ChangeLog b/ChangeLog
index 427f1bcb3..b108ebb88 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2023-04-16  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       [build]: Improve portability to non-GNU, non-LLVM compilers.
+
+       * bootstrap.conf (gnulib_modules): Add "attribute".
+       * src/libs/libgroff/getopt.c:
+       * src/libs/libgroff/new.cpp: Include gnulib's "attribute.h"
+       header file.
+       * src/libs/libgroff/getopt.c (_getopt_initialize):
+       * src/libs/libgroff/new.cpp (operator delete): Replace GNU C
+       unused attribute syntax with gnulib's "MAYBE_UNUSED".
+
+       Thanks to Bruno Haible for the report and suggested remedy.
+
 2023-03-16  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        * src/libs/libxutil/XFontName.c (utoa): Rename function from
diff --git a/bootstrap.conf b/bootstrap.conf
index 7a2099fb8..aa96ac6df 100644
--- a/bootstrap.conf
+++ b/bootstrap.conf
@@ -36,6 +36,7 @@ checkout_only_file=README.git
 # havelib provides config.rpath
 # can be get through gettext though
 gnulib_modules="
+    attribute
     git-version-gen
     havelib
     wcwidth
diff --git a/src/libs/libgroff/getopt.c b/src/libs/libgroff/getopt.c
index 6efa5299b..2bf2eee8e 100644
--- a/src/libs/libgroff/getopt.c
+++ b/src/libs/libgroff/getopt.c
@@ -28,6 +28,8 @@
 # include <config.h>
 #endif
 
+#include <attribute.h> // gnulib: MAYBE_UNUSED
+
 #include <stdio.h>
 
 /* This needs to come after some library #include
@@ -248,8 +250,7 @@ exchange (char **argv, struct _getopt_data *d)
 /* Initialize the internal data when the first call is made.  */
 
 static const char *
-_getopt_initialize (__attribute__((__unused__)) int argc,
-                   __attribute__((__unused__)) char **argv,
+_getopt_initialize (MAYBE_UNUSED int argc, MAYBE_UNUSED char **argv,
                    const char *optstring, int posixly_correct,
                    struct _getopt_data *d)
 {
diff --git a/src/libs/libgroff/new.cpp b/src/libs/libgroff/new.cpp
index 2af976cf4..73b24efd9 100644
--- a/src/libs/libgroff/new.cpp
+++ b/src/libs/libgroff/new.cpp
@@ -16,6 +16,8 @@ for more details.
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>. */
 
+#include <attribute.h> // gnulib: MAYBE_UNUSED
+
 #include "lib.h"
 
 #include <stddef.h>
@@ -54,8 +56,7 @@ void operator delete(void *p) throw()
     free(p);
 }
 
-void operator delete(void *p,
-                    __attribute__((__unused__)) long unsigned int size)
+void operator delete(void *p, MAYBE_UNUSED long unsigned int size)
 {
   // It's ugly to duplicate the code from delete(void *) above, but if
   // we don't, g++ 6.3 can't figure out we're calling through it to