Remove PHP atomic includes and PHP_DEFINE M4 macro (#13372)

PHP_DEFINE was introduced with the PHP 5 build system
9d9d39a0de and then refactored via
350de12bc2.

This was once used to put defined constants into a single file to have
more fine-graned dependencies (atomic includes). Since no known PHP
extension is using this and it makes very little sense to use this, this
M4 macro can be removed in favor of the Autoconf native way using
AC_DEFINE and the usual included files php_config.h and config.h.

- Generated unused include directory removed
- Remove include dir from DEFS
- Remove also include dir from PDO checks

.gitignore

@@ -79,7 +79,6 @@ Makefile.fragments
 Makefile.objects
 
 # Directories for shared object files and headers generated by `./configure`
-include/
 libs/
 modules/
 

UPGRADING.INTERNALS

@@ -63,6 +63,7 @@ PHP 8.4 INTERNALS UPGRADE NOTES
    - Symbol DARWIN has been removed (use __APPLE__ to target Darwin systems).
    - Symbol MISSING_FCLOSE_DECL and M4 macro PHP_MISSING_FCLOSE_DECL removed.
    - Symbol HAVE_BSD_ICONV has been removed.
+   - M4 macro PHP_DEFINE (atomic includes) removed (use AC_DEFINE and config.h).
 
  c. Windows build system changes
    - The configure options --with-oci8-11g, --with-oci8-12c, --with-oci8-19 have

build/Makefile.global

@@ -2,7 +2,7 @@ mkinstalldirs = $(top_srcdir)/build/shtool mkdir -p
 INSTALL = $(top_srcdir)/build/shtool install -c
 INSTALL_DATA = $(INSTALL) -m 644
 
-DEFS = -I$(top_builddir)/include -I$(top_builddir)/main -I$(top_srcdir)
+DEFS = -I$(top_builddir)/main -I$(top_srcdir)
 COMMON_FLAGS = $(DEFS) $(INCLUDES) $(EXTRA_INCLUDES) $(CPPFLAGS) $(PHP_FRAMEWORKPATH)
 
 all: $(all_targets)
@@ -135,7 +135,6 @@ distclean: clean
 	if test "$(srcdir)" != "$(builddir)"; then \
 	  rm -f ext/phar/phar/phar.inc; \
 	fi
-	$(EGREP) define'.*include/php' $(top_srcdir)/configure | $(SED) 's/.*>//'|xargs rm -f
 
 prof-gen:
 	CCACHE_DISABLE=1 $(MAKE) PROF_FLAGS=-fprofile-generate all

build/php.m4

@@ -69,15 +69,6 @@ AC_DEFUN([PHP_EXPAND_PATH],[
   fi
 ])
 
-dnl
-dnl PHP_DEFINE(WHAT [, value[, directory]])
-dnl
-dnl Creates builddir/include/what.h and in there #define WHAT value.
-dnl
-AC_DEFUN([PHP_DEFINE],[
-  [echo "#define ]$1[]ifelse([$2],,[ 1],[ $2])[" > ]ifelse([$3],,[include],[$3])[/php_]translit($1,A-Z,a-z)[.h]
-])
-
 dnl
 dnl PHP_SUBST(varname)
 dnl
@@ -135,12 +126,8 @@ dnl Creates build directories and Makefile placeholders.
 dnl
 AC_DEFUN([PHP_INIT_BUILD_SYSTEM],[
 AC_REQUIRE([PHP_CANONICAL_HOST_TARGET])dnl
-test -d include || $php_shtool mkdir include
 > Makefile.objects
 > Makefile.fragments
-dnl We need to play tricks here to avoid matching the grep line itself.
-pattern=define
-$EGREP $pattern'.*include/php' $srcdir/configure|$SED 's/.*>//'|xargs touch 2>/dev/null
 ])
 
 dnl
@@ -2115,9 +2102,7 @@ dnl PHP_CHECK_PDO_INCLUDES([found [, not-found]])
 dnl
 AC_DEFUN([PHP_CHECK_PDO_INCLUDES],[
   AC_CACHE_CHECK([for PDO includes], pdo_cv_inc_path, [
-    if test -f $abs_srcdir/include/php/ext/pdo/php_pdo_driver.h; then
+    if test -f $abs_srcdir/ext/pdo/php_pdo_driver.h; then
-      pdo_cv_inc_path=$abs_srcdir/ext
-    elif test -f $abs_srcdir/ext/pdo/php_pdo_driver.h; then
       pdo_cv_inc_path=$abs_srcdir/ext
     elif test -f $phpincludedir/ext/pdo/php_pdo_driver.h; then
       pdo_cv_inc_path=$phpincludedir/ext

configure.ac

@@ -1692,7 +1692,7 @@ PHP_SUBST(all_targets)
 PHP_SUBST(install_targets)
 PHP_SUBST(install_binary_targets)
 
-PHP_INSTALL_HEADERS([Zend/ TSRM/ include/ main/ main/streams/])
+PHP_INSTALL_HEADERS([Zend/ TSRM/ main/ main/streams/])
 PHP_INSTALL_HEADERS([Zend/Optimizer], [ \
     zend_call_graph.h \
     zend_cfg.h \

docs/unix-build-system.md

@@ -7,8 +7,6 @@
   especially noticeable on slower systems
 * slow recursive make replaced with one global Makefile
 * eases integration of proper dependencies
-* adds PHP_DEFINE(what[, value]) which creates a single include-file per what.
-  This will allow more fine-grained dependencies.
 * abandoning the "one library per directory" concept
 * improved integration of the CLI
 * several new targets: