[PR build/29791] gnulib: Disable _GL_ATTRIBUTE_DEALLOC on Solaris

gdbsupport compilation badly fails with GCC 12 on Solaris, with errors
like

../gnulib/config.h:1693:72: error: ‘malloc’ attribute argument 1 is ambiguous
 1693 | # define _GL_ATTRIBUTE_DEALLOC(f, i) __attribute__ ((__malloc__ (f, i)))
      |                                                                        ^
../gnulib/config.h:1693:72: note: use a cast to the expected type to disambiguate

We've not yet been able to determine where the ambiguity actually lies,
so this patch works around the issue by disabling _GL_ATTRIBUTE_DEALLOC
on Solaris, at least as a workaround for GDB 13.

As Tom suggested in the PR, this is done using our infrastructure for
local gnulib patches.

Tested on sparcv9-sun-solaris2.11, amd64-pc-solaris2.11, and
x86_64-pc-linux-gnu.

Approved-By: Simon Marchi <simon.marchi@efficios.com>

gnulib/config.in

@@ -1688,7 +1688,8 @@
    _GL_ATTRIBUTE_DEALLOC_FREE declares that the function returns pointers that
    can be freed via 'free'; it can be used only after declaring 'free'.  */
 /* Applies to: functions.  Cannot be used on inline functions.  */
-#if _GL_GNUC_PREREQ (11, 0)
+/* Disable on Solaris to avoid GDB PR build/29791.  */
+#if _GL_GNUC_PREREQ (11, 0) && !(defined(__sun__) && defined(__svr4__))
 # define _GL_ATTRIBUTE_DEALLOC(f, i) __attribute__ ((__malloc__ (f, i)))
 #else
 # define _GL_ATTRIBUTE_DEALLOC(f, i)

gnulib/import/m4/gnulib-common.m4

@@ -182,7 +182,8 @@ AC_DEFUN([gl_COMMON_BODY], [
    _GL_ATTRIBUTE_DEALLOC_FREE declares that the function returns pointers that
    can be freed via 'free'; it can be used only after declaring 'free'.  */
 /* Applies to: functions.  Cannot be used on inline functions.  */
-#if _GL_GNUC_PREREQ (11, 0)
+/* Disable on Solaris to avoid GDB PR build/29791.  */
+#if _GL_GNUC_PREREQ (11, 0) && !(defined(__sun__) && defined(__svr4__))
 # define _GL_ATTRIBUTE_DEALLOC(f, i) __attribute__ ((__malloc__ (f, i)))
 #else
 # define _GL_ATTRIBUTE_DEALLOC(f, i)

gnulib/patches/0002-no-solaris-_gl_attribute_dealloc

@@ -0,0 +1,13 @@
+diff --git a/gnulib/import/m4/gnulib-common.m4 b/gnulib/import/m4/gnulib-common.m4
+--- a/gnulib/import/m4/gnulib-common.m4
++++ b/gnulib/import/m4/gnulib-common.m4
+@@ -182,7 +182,8 @@ AC_DEFUN([gl_COMMON_BODY], [
+    _GL_ATTRIBUTE_DEALLOC_FREE declares that the function returns pointers that
+    can be freed via 'free'; it can be used only after declaring 'free'.  */
+ /* Applies to: functions.  Cannot be used on inline functions.  */
+-#if _GL_GNUC_PREREQ (11, 0)
++/* Disable on Solaris to avoid GDB PR build/29791.  */
++#if _GL_GNUC_PREREQ (11, 0) && !(defined(__sun__) && defined(__svr4__))
+ # define _GL_ATTRIBUTE_DEALLOC(f, i) __attribute__ ((__malloc__ (f, i)))
+ #else
+ # define _GL_ATTRIBUTE_DEALLOC(f, i)

gnulib/update-gnulib.sh

@@ -188,6 +188,7 @@ apply_patches ()
 }
 
 apply_patches "patches/0001-use-windows-stat"
+apply_patches "patches/0002-no-solaris-_gl_attribute_dealloc"
 
 # Regenerate all necessary files...
 aclocal &&