From 58d431568d6b6163dd9cdc920239f173689a769c Mon Sep 17 00:00:00 2001
From: Martin Liska <mliska@suse.cz>
Date: Fri, 4 Feb 2022 13:42:14 +0100
Subject: [PATCH] configure: add --disable-fix-includes

Right now, fixinclude takes about 11 seconds on my machine, where
it reads 130MB of header files.

The number of fixed headers is negligible without any significant
change.

fixincludes/ChangeLog:

	* fixinc.in: Add early exit.

gcc/ChangeLog:

	* Makefile.in: Support disable_fix_includes.
	* configure.ac: Add --disable-fix-includes.
	* configure: Regenerate.
	* doc/install.texi: Document the newly added configure options.
---
 fixincludes/fixinc.in |  6 ++++++
 gcc/Makefile.in       |  6 ++++--
 gcc/configure         | 16 ++++++++++++++--
 gcc/configure.ac      |  6 ++++++
 gcc/doc/install.texi  |  7 +++++++
 5 files changed, 37 insertions(+), 4 deletions(-)

diff --git a/fixincludes/fixinc.in b/fixincludes/fixinc.in
index 0bd8027a554..9baec3f871d 100755
--- a/fixincludes/fixinc.in
+++ b/fixincludes/fixinc.in
@@ -63,6 +63,12 @@ else
   esac
 fi
 
+if test "x$ENABLE_FIX_INCLUDES" = "xno"
+then
+  echo "Skipping fixincludes"
+  exit 0
+fi
+
 # Define what target system we're fixing.
 #
 if test -r ./Makefile; then
diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index 31ff95500c9..80de547231a 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -401,6 +401,8 @@ PLUGINLIBS = @pluginlibs@
 
 enable_plugin = @enable_plugin@
 
+enable_fix_includes = @enable_fix_includes@
+
 # On MinGW plugin installation involves installing import libraries.
 ifeq ($(enable_plugin),yes)
   plugin_implib := $(if $(strip $(filter mingw%,$(host_os))),yes,no)
@@ -3248,8 +3250,8 @@ stmp-fixinc: gsyslimits.h macro_list fixinc_list \
 	    chmod a+rx $${fix_dir} || true; \
 	    (TARGET_MACHINE='$(target)'; srcdir=`cd $(srcdir); ${PWD_COMMAND}`; \
 	      SHELL='$(SHELL)'; MACRO_LIST=`${PWD_COMMAND}`/macro_list ; \
-	      gcc_dir=`${PWD_COMMAND}` ; \
-	      export TARGET_MACHINE srcdir SHELL MACRO_LIST && \
+	      gcc_dir=`${PWD_COMMAND}` ; ENABLE_FIX_INCLUDES=${enable_fix_includes} \
+	      export TARGET_MACHINE srcdir SHELL MACRO_LIST ENABLE_FIX_INCLUDES && \
 	      cd $(build_objdir)/fixincludes && \
 	      $(SHELL) ./fixinc.sh "$${gcc_dir}/$${fix_dir}" \
 	        $(BUILD_SYSTEM_HEADER_DIR) $(OTHER_FIXINCLUDES_DIRS) ); \
diff --git a/gcc/configure b/gcc/configure
index 5ce0557719a..e29f2cf7d2e 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -839,6 +839,7 @@ with_float
 with_cpu
 enable_multiarch
 enable_multilib
+enable_fix_includes
 coverage_flags
 valgrind_command
 valgrind_path_defines
@@ -958,6 +959,7 @@ enable_werror_always
 enable_checking
 enable_coverage
 enable_gather_detailed_mem_stats
+enable_fix_includes
 enable_valgrind_annotations
 enable_multilib
 enable_multiarch
@@ -1688,6 +1690,7 @@ Optional Features:
                           Values are opt, noopt, default is noopt
   --enable-gather-detailed-mem-stats
                           enable detailed memory allocation stats gathering
+  --disable-fix-includes  skip fixing of includes
   --enable-valgrind-annotations
                           enable valgrind runtime interaction
   --enable-multilib       enable library support for multiple ABIs
@@ -7783,6 +7786,15 @@ cat >>confdefs.h <<_ACEOF
 _ACEOF
 
 
+# Check whether --enable-fix-includes was given.
+if test "${enable_fix_includes+set}" = set; then :
+  enableval=$enable_fix_includes;
+else
+  enable_fix_includes=yes
+fi
+
+
+
 # Check whether --enable-valgrind-annotations was given.
 if test "${enable_valgrind_annotations+set}" = set; then :
   enableval=$enable_valgrind_annotations;
@@ -19673,7 +19685,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 19676 "configure"
+#line 19688 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -19779,7 +19791,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 19782 "configure"
+#line 19794 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
diff --git a/gcc/configure.ac b/gcc/configure.ac
index 23bee7010a3..0e20435d38b 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -842,6 +842,12 @@ gather_stats=`if test $enable_gather_detailed_mem_stats != no; then echo 1; else
 AC_DEFINE_UNQUOTED(GATHER_STATISTICS, $gather_stats,
 [Define to enable detailed memory allocation stats gathering.])
 
+AC_ARG_ENABLE(fix-includes,
+[AS_HELP_STRING([--disable-fix-includes],
+		[skip fixing of includes])], [],
+[enable_fix_includes=yes])
+AC_SUBST(enable_fix_includes)
+
 AC_ARG_ENABLE(valgrind-annotations,
 [AS_HELP_STRING([--enable-valgrind-annotations],
 		[enable valgrind runtime interaction])], [],
diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi
index 10bfceffceb..c1404b4947e 100644
--- a/gcc/doc/install.texi
+++ b/gcc/doc/install.texi
@@ -2371,6 +2371,13 @@ For a native build and cross compiles that have target headers, the option's
 default is derived from glibc's behavior. When glibc clamps float_t to double,
 GCC follows and enables the option. For other cross compiles, the default is
 disabled.
+
+@item --enable-fix-include
+@itemx --disable-fix-include
+
+Enable fixing of system header files. GCC needs to install corrected versions
+of some system header files. This is because most target systems have
+some header files that won’t work with GCC unless they are changed.
 @end table
 
 @subheading Cross-Compiler-Specific Options
-- 
2.36.1