[PATCH 4/6] autoregen.py: Use autoreconf in most GCC directories

[Christophe Lyon <christophe.lyon@linaro.org>]

Add most of GCC's subdirectories to AUTORECONF_DIRS, since 'autoreconf
-f' works for them.

A few subdirs still need to be regenerated "manually", because they do
not have Makefile.am which autoreconf uses to determine which aclocal
flags to use.

Most use our default aclocal -I../config, but a few need special
flags, which I copied from the corresponding Makefile.in:
* fixincludes: -I.. -I../config
* gcc, libiberty, libobjc: -I../config -I..
* libgm2: -I../config -I.. although Makefile.in says otherwise. Using
  what Makefile.in defines results in generating aclocal.m4 with a
  different contents than what it is in the repo. The repo is
  presumably wrong, but use this until this is fixed.

Note that we do not regenerate
libvtv/testsuite/other-tests/Makefile.in, because
libvtv/testsuite/other-tests/ has no configure.ac.

Running this script over GCC's repository generates quite a few
warnings, which are the same as before this patch. Namely, these
subdirs seem to have incorrect autotools files (at least partially):
* libgfortran
* libgomp
* libsanitizer

This patch does not support regenerating gcc/m2/gm2-libs/config-host
and gcc/m2/gm2-libs/gm2-libs-host.h.in because I didn't manage to
regenerate them with the exact same content. FTR I tried:
autoconf -f config-host.in > config-host
autoheader config-host.in
as described in gcc/m2/Make-maintainer.in

Similarly, we skip libcpp because the files we regenerate have small
differences with the current versions.

Tested by removing all aclocal.m4 files, Makefile.in files derived
from Makefile.am, configure files derived from configure.ac and
checking they are correctly regenerated (that is, 'git status' does
not report deleted nor modified files).
---
 builder/containers/autoregen.py | 60 ++++++++++++++++++++++++++++++++-
 1 file changed, 59 insertions(+), 1 deletion(-)

diff --git a/builder/containers/autoregen.py b/builder/containers/autoregen.py
index c52a524..4731a87 100755
--- a/builder/containers/autoregen.py
+++ b/builder/containers/autoregen.py
@@ -40,15 +40,56 @@ SKIP_DIRS = [
     # readline and minizip are maintained with different autotools versions
     "readline",
     "minizip",
+
+    # aclocal.m4 gets an additional ../config/override.m4,
+    # and config.in gets a few more empty lines.
+    "libcpp",
 ]
 
 # these directories are known to can be re-generatable with a simple autoreconf
 # without special -I flags
 AUTORECONF_DIRS = [
+    # binutils-gdb subdirs
     "gdb",
     "gdbserver",
     "gdbsupport",
     "gnulib",
+
+    # gcc subdirs
+    "c++tools", # No aclocal.m4
+    #"gcc", # No Makefile.am
+    #"fixincludes", # autoreconf complains about GCC_AC_FUNC_MMAP_BLACKLIST
+    "gnattools", # No aclocal.m4
+    "gotools",
+    "libada", # No aclocal.m4
+    "libatomic",
+    "libbacktrace",
+    "libcc1",
+    "libcody", # No aclocal.m4
+    #"libcpp", # No Makefile.am
+    #"libdecnumber", # No Makefile.am
+    "libffi",
+    "libgcc", # No aclocal.m4
+    "libgfortran",
+    # Hack: ACLOCAL_AMFLAGS = -I .. -I ../config in Makefile.in but we
+    # apply -I../config -I.. otherwise we do not match the current
+    # contents
+    #"libgm2",
+    "libgo",
+    "libgomp",
+    "libgrust",
+    #"libiberty", # No Makefile.am
+    "libitm",
+    #"libobjc", # No Makefile.am
+    "libphobos",
+    "libquadmath",
+    "libsanitizer",
+    "libssp",
+    "libstdc++-v3",
+    # This does not cover libvtv/testsuite/other-tests/Makefile.in
+    "libvtv",
+    "lto-plugin",
+    "zlib",
 ]
 
 
@@ -71,7 +112,9 @@ def regenerate_with_autoreconf():
 
 def regenerate_manually():
     configure_lines = open("configure.ac").read().splitlines()
-    if any(True for line in configure_lines if line.startswith("AC_CONFIG_MACRO_DIR")):
+    if folder.stem == "fixincludes" or folder.stem == "libgm2" or any(
+            True for line in configure_lines if line.startswith("AC_CONFIG_MACRO_DIR")
+    ):
         include_arg = ""
         include_arg2 = ""
         if (folder / ".." / "config").is_dir():
@@ -83,6 +126,14 @@ def regenerate_manually():
             include_arg = "-I../.."
             include_arg2 = "-I../../config"
 
+        if folder.stem == "fixincludes":
+            include_arg = "-I.."
+            include_arg2 = "-I../config"
+
+        if folder.stem == "libgm2" or folder.stem == "gcc" or folder.stem == "libiberty" or folder.stem == "libobjc":
+            include_arg = "-I../config"
+            include_arg2 = "-I.."
+
         # aclocal does not support the -f short option for force
         run_shell(f"{ACLOCAL_BIN} --force {include_arg} {include_arg2}")
 
@@ -91,6 +142,13 @@ def regenerate_manually():
     ):
         run_shell(f"{AUTOHEADER_BIN} -f")
 
+    # The few lines below do not regenerate the exact same content as
+    # currently in the repo. Disable them for now.
+    # if (folder / "gm2-libs").is_dir():
+    #     run_shell(f"{AUTOCONF_BIN} -f gm2-libs/config-host.in > gm2-libs/config-host")
+    #     run_shell(f"{AUTOHEADER_BIN} gm2-libs/config-host.in")
+
+
     # apparently automake is somehow unstable -> skip it for gotools
     if any(
         True for line in configure_lines if line.startswith("AM_INIT_AUTOMAKE")
-- 
2.34.1