Auto-generate libc-modules.h

Remove libc-modules.h from the tree and auto-generate it from
soversions.i and a new file build.list.  Macros generated from
soversions.i have lower values starting from 1, while those from
build.list start from a special value MODULE_OTHER_BEGIN, which has a
high enough value (1000).  This allows us to conveniently
differentiate between the versioned libraries and other built modules,
which is needed in errno.h and netdb.h to decide whether to use an
internal symbol or an external one.

Verified that generated code remains unchanged on x86_64.

	* Makeconfig (module-cppflags): Include libc-modules.h for
	everything except shlib-versions.v.i.
	(CPPFLAGS): Use it.
	(before-compile): Add libc-modules.h.
	($(common-objpfx)libc-modules.h,
	$(common-objpfx)libc-modules.stmp): New targets.
	(common-generated): Add libc-modules.h and libc-modules.stmp.
	($(common-objpfx)Versions.v.i): Depend on libc-modules.h.
	* build.list: New file.
	* include/libc-symbols.h: Don't include libc-modules.h.
	* include/libc-modules.h: Remove file.
	* scripts/gen-libc-modules.awk: New script to generate
	libc-modules.h.
	* sysdeps/unix/Makefile ($(common-objpfx)sysd-syscalls):
	Depend on libc-modules.stmp.

diff --git a/Makeconfig b/Makeconfig
index 671eceb40a8e37607e95a08183056c94192d8a9d..5ffbd92cce79a7093efcf2d54760afa0f577b027 100644 (file)
--- a/Makeconfig
+++ b/Makeconfig
@@ -813,10 +813,22 @@ endif     # $(+cflags) == ""
 # of many little headers in the include directory.
 libio-include = -I$(..)libio
 
+# We don't include libc-modules.h when these targets are being built.  These
+# targets don't (and will likely never need to) use the IS_IN facility.  In
+# fact, shlib-versions should not use it because that will create a circular
+# dependency as libc-modules.h is generated from shlib-versions.
+skip-module-cppflags = shlib-versions.v.i Versions.v.i
+
 in-module = $(strip $(foreach lib,$(libof-$(basename $(@F))) $(libof-$(<F)) \
                                  $(libof-$(@F)),-DIN_MODULE=MODULE_$(lib)))
 
 module-def = $(if $(in-module),$(in-module),-DIN_MODULE=MODULE_libc)
+module-cppflags-real = -include $(common-objpfx)libc-modules.h $(module-def)
+
+# We don't need libc-modules.h and the IN_MODULE definition for
+# shlib-version.v.i.
+module-cppflags = $(if $(filter $(@F),$(skip-module-cppflags)), \
+                      ,$(module-cppflags-real))
 
 # These are the variables that the implicit compilation rules use.
 # Note that we can't use -std=* in CPPFLAGS, because it overrides
@@ -824,9 +836,9 @@ module-def = $(if $(in-module),$(in-module),-DIN_MODULE=MODULE_libc)
 # it causes cpp to stop predefining __ASSEMBLER__.
 CPPFLAGS = $(config-extra-cppflags) $(CPPUNDEFS) $(CPPFLAGS-config) \
           $($(subdir)-CPPFLAGS) \
-          $(+includes) $(defines) \
+          $(+includes) $(defines) $(module-cppflags) \
           -include $(..)include/libc-symbols.h $(sysdep-CPPFLAGS) \
-          $(CPPFLAGS-$(suffix $@)) $(module-def) \
+          $(CPPFLAGS-$(suffix $@)) \
           $(foreach lib,$(libof-$(basename $(@F))) \
                         $(libof-$(<F)) $(libof-$(@F)),$(CPPFLAGS-$(lib))) \
           $(CPPFLAGS-$(<F)) $(CPPFLAGS-$(@F)) $(CPPFLAGS-$(basename $(@F)))
@@ -986,6 +998,24 @@ endif
 postclean-generated += soversions.mk soversions.i \
                       shlib-versions.v shlib-versions.v.i
 
+before-compile += $(common-objpfx)libc-modules.h
+ifeq ($(soversions.mk-done),t)
+# Generate a header with macro definitions for use with the IS_IN macro.
+# These are the possible values for the IN_MODULE macro defined when building
+# sources, to identify which module the translation unit is going to be built
+# into.
+$(common-objpfx)libc-modules.h: $(common-objpfx)libc-modules.stmp; @:
+$(common-objpfx)libc-modules.stmp: $(..)scripts/gen-libc-modules.awk \
+                                  $(common-objpfx)soversions.i \
+                                  $(..)build.list
+       $(AWK) -f $^ > ${@:stmp=T}
+       $(move-if-change) ${@:stmp=T} ${@:stmp=h}
+       touch $@
+
+endif
+
+common-generated += libc-modules.h libc-modules.stmp
+
 # The name under which the run-time dynamic linker is installed.
 # We are currently going for the convention that `/lib/ld.so.1'
 # names the SVR4/ELF ABI-compliant dynamic linker.

diff --git a/build.list b/build.list
new file mode 100644 (file)
index 0000000..eab57c7
--- /dev/null
+++ b/build.list
@@ -0,0 +1,15 @@
+iconvprogs
+iconvdata
+ldconfig
+lddlibc4
+libmemusage
+libSegFault
+libpcprofile
+librpcsvc
+libutil
+locale_programs
+memusagestat
+nonlib
+nscd
+extramodules
+libnldbl

diff --git a/include/libc-modules.h b/include/libc-modules.h
deleted file mode 100644 (file)
index d12fb90..0000000
--- a/include/libc-modules.h
+++ /dev/null
@@ -1,37 +0,0 @@
-#define MODULE_libc            1
-#define MODULE_libpthread      2
-#define MODULE_rtld            3
-#define MODULE_libdl           4
-#define MODULE_libm            5
-#define MODULE_iconvprogs      6
-#define MODULE_iconvdata       7
-#define MODULE_lddlibc4                8
-#define MODULE_locale_programs 9
-#define MODULE_memusagestat    10
-#define MODULE_libutil         12
-#define MODULE_libBrokenLocale 13
-#define MODULE_libmemusage     15
-#define MODULE_libresolv       16
-#define MODULE_libnss_db       17
-#define MODULE_libnss_files    18
-#define        MODULE_libnss_dns       19
-#define MODULE_libnss_compat   20
-#define MODULE_libnss_hesiod   21
-#define MODULE_libnss_nis      22
-#define MODULE_libnss_nisplus  23
-#define MODULE_libanl          24
-#define MODULE_librt           25
-#define MODULE_libSegFault     26
-#define MODULE_libthread_db    27
-#define MODULE_libcidn         28
-#define MODULE_libcrypt                29
-#define MODULE_libnsl          30
-#define MODULE_libpcprofile    31
-#define MODULE_librpcsvc       32
-#define MODULE_nscd            33
-#define MODULE_ldconfig        34
-#define MODULE_libnldbl        35
-
-/* Catch-all for test modules and other binaries.  */
-#define MODULE_nonlib          98
-#define MODULE_extramodules    99

diff --git a/include/libc-symbols.h b/include/libc-symbols.h
index 131d7ebd37ac92393088380c1ce5cc99af58a836..9b8208b1837a31bcae145688bbeb17473145865a 100644 (file)
--- a/include/libc-symbols.h
+++ b/include/libc-symbols.h
@@ -20,8 +20,6 @@
 #ifndef _LIBC_SYMBOLS_H
 #define _LIBC_SYMBOLS_H        1
 
-#include "libc-modules.h"
-
 #define IS_IN(lib) (IN_MODULE == MODULE_##lib)
 
 /* This file's macros are included implicitly in the compilation of every

diff --git a/scripts/gen-libc-modules.awk b/scripts/gen-libc-modules.awk
new file mode 100644 (file)
index 0000000..d3382b6
--- /dev/null
+++ b/scripts/gen-libc-modules.awk
@@ -0,0 +1,40 @@
+# Generate a header file that defines the MODULE_* macros for each library and
+# module we build in glibc.  The library names are pulled in from soversions.i
+# and the additional modules are mentioned one-per-line in build.list.
+BEGIN {
+  PROCINFO["sorted_in"] = "@val_type_asc"
+  shlibs = 1
+  others = 1000
+  libs["OTHERS_BEGIN"] = others++
+}
+
+# Skip over comments.
+$1 == "#" {
+  next
+}
+
+# build.list is simply one module per line.
+match (FILENAME, ".*build.list") {
+  libs[$0] = others++
+}
+
+# We have only one special case in soversions.i parsing, which is to replace ld
+# with rtld since that's what we call it throughout the sources.
+match (FILENAME, ".*soversions.i") {
+  name = $2
+  if (name == "ld")
+    name = "rtld"
+
+  if (!(name in libs)) {
+    libs[name] = shlibs++
+  }
+}
+
+# Finally, print out the header file.
+END {
+  printf ("/* AUTOGENERATED BY gen-libc-modules.awk, DO NOT EDIT.  */\n\n")
+  i = 1
+  for (l in libs) {
+    printf ("#define MODULE_%s %d\n", l, libs[l])
+  }
+}

diff --git a/sysdeps/unix/Makefile b/sysdeps/unix/Makefile
index 0e535b63f9b6d91b857f3ad689265df7085598b6..573e90d57fbc234394e413add7cc9ad81af112e0 100644 (file)
--- a/sysdeps/unix/Makefile
+++ b/sysdeps/unix/Makefile
@@ -79,7 +79,8 @@ compile-syscall = $(COMPILE.S) -o $@ -x assembler-with-cpp - \
 
 ifndef avoid-generated
 $(common-objpfx)sysd-syscalls: $(..)sysdeps/unix/make-syscalls.sh \
-                              $(wildcard $(+sysdep_dirs:%=%/syscalls.list))
+                              $(wildcard $(+sysdep_dirs:%=%/syscalls.list)) \
+                              $(common-objpfx)libc-modules.stmp
        for dir in $(+sysdep_dirs); do \
          test -f $$dir/syscalls.list && \
          { sysdirs='$(sysdirs)' \