Support after-link variable to run a final step on binaries.

diff --git a/ChangeLog b/ChangeLog
index 986554f..bd06443 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2015-02-12  Roland McGrath  <roland@hack.frob.com>
+
+       * Makeconfig (after-link): New variable.
+       (+link-pie, +link-pie-tests): Use it.
+       (+link-static, +link-static-tests): Likewise.
+       (+link, +link-tests): Likewise.
+       * Makerules (build-module, build-module-asneeded): Likewise.
+       (lib%.so, $(common-objpfx)libc.so, $(common-objpfx)linkobj/libc.so):
+       Likewise.
+       * elf/Makefile ($(objpfx)ld.so): Likewise.
+
 2015-02-12  Rüdiger Sonderfeld  <ruediger@c-plusplus.net>
 
        [BZ #17965]

diff --git a/Makeconfig b/Makeconfig
index 751e9ff..1e03481 100644 (file)
--- a/Makeconfig
+++ b/Makeconfig
@@ -387,6 +387,14 @@ LDFLAGS.so += $(hashstyle-LDFLAGS)
 LDFLAGS-rtld += $(hashstyle-LDFLAGS)
 endif
 
+# Command to run after every final link (executable or shared object).
+# This is invoked with $(call after-link,...), so it should operate on
+# the file $1.  This can be set to do some sort of post-processing on
+# binaries, or to perform some sort of static sanity check.
+ifndef after-link
+after-link =
+endif
+
 # Command for linking PIE programs with the C library.
 ifndef +link-pie
 +link-pie-before-libc = $(CC) -pie -Wl,-O1 -nostdlib -nostartfiles -o $@ \
@@ -400,10 +408,15 @@ ifndef +link-pie
                          $(common-objpfx)libc% $(+postinit),$^) \
             $(link-extra-libs)
 +link-pie-after-libc = $(+postctorS) $(+postinit)
-+link-pie = $(+link-pie-before-libc) $(rtld-LDFLAGS) $(link-libc) \
-           $(+link-pie-after-libc)
-+link-pie-tests = $(+link-pie-before-libc) $(rtld-tests-LDFLAGS) \
-                 $(link-libc-tests) $(+link-pie-after-libc)
+define +link-pie
+$(+link-pie-before-libc) $(rtld-LDFLAGS) $(link-libc) $(+link-pie-after-libc)
+$(call after-link,$@)
+endef
+define +link-pie-tests
+$(+link-pie-before-libc) $(rtld-tests-LDFLAGS) $(link-libc-tests) \
+                        $(+link-pie-after-libc)
+$(call after-link,$@)
+endef
 endif
 # Command for statically linking programs with the C library.
 ifndef +link-static
@@ -417,10 +430,14 @@ ifndef +link-static
                           $(common-objpfx)libc% $(+postinit),$^) \
              $(link-extra-libs-static)
 +link-static-after-libc = $(+postctorT) $(+postinit)
-+link-static = $(+link-static-before-libc) $(link-libc-static) \
-              $(+link-static-after-libc)
-+link-static-tests = $(+link-static-before-libc) $(link-libc-static-tests) \
-                    $(+link-static-after-libc)
+define +link-static
+$(+link-static-before-libc) $(link-libc-static) $(+link-static-after-libc)
+$(call after-link,$@)
+endef
+define +link-static-tests
+$(+link-static-before-libc) $(link-libc-static-tests) $(+link-static-after-libc)
+$(call after-link,$@)
+endef
 endif
 # Commands for linking programs with the C library.
 ifndef +link
@@ -436,10 +453,15 @@ ifeq (yes,$(build-shared))
                           $(common-objpfx)libc% $(+postinit),$^) \
              $(link-extra-libs)
 +link-after-libc = $(+postctor) $(+postinit)
-+link = $(+link-before-libc) $(rtld-LDFLAGS) $(link-libc) \
-       $(+link-after-libc)
-+link-tests = $(+link-before-libc) $(rtld-tests-LDFLAGS) \
-             $(link-libc-tests) $(+link-after-libc)
+define +link
+$(+link-before-libc) $(rtld-LDFLAGS) $(link-libc) $(+link-after-libc)
+$(call after-link,$@)
+endef
+define +link-tests
+$(+link-before-libc) $(rtld-tests-LDFLAGS) $(link-libc-tests) \
+                    $(+link-after-libc)
+$(call after-link,$@)
+endef
 else
 +link = $(+link-static)
 +link-tests = $(+link-static-tests)

diff --git a/Makerules b/Makerules
index ca238f1..c79915f 100644 (file)
--- a/Makerules
+++ b/Makerules
@@ -505,6 +505,7 @@ link-libc-deps = $(common-objpfx)libc.so $(common-objpfx)linkobj/libc.so \
 # to be as similar as possible to a default link with an installed libc.
 lib%.so: lib%_pic.a $(+preinit) $(+postinit) $(link-libc-deps)
        $(build-shlib) $(link-libc-args)
+       $(call after-link,$@)
 
 define build-shlib-helper
 $(LINK.o) -shared $(static-libgcc) -Wl,-O1 $(sysdep-LDFLAGS) \
@@ -580,12 +581,14 @@ endef
 define build-module
 $(build-module-helper) -o $@ $(shlib-lds-flags) \
          $(csu-objpfx)abi-note.o $(build-module-objlist) $(link-libc-args)
+$(call after-link,$@)
 endef
 define build-module-asneeded
 $(build-module-helper) -o $@ $(shlib-lds-flags) \
          $(csu-objpfx)abi-note.o \
          -Wl,--as-needed $(build-module-objlist) -Wl,--no-as-needed \
          $(link-libc-args)
+$(call after-link,$@)
 endef
 
 build-module-helper-objlist = \
@@ -666,6 +669,7 @@ $(common-objpfx)libc.so: $(elf-objpfx)soinit.os \
                         $(elf-objpfx)ld.so \
                         $(shlib-lds)
        $(build-shlib)
+       $(call after-link,$@)
 
 $(common-objpfx)linkobj/libc.so: $(elf-objpfx)soinit.os \
                         $(common-objpfx)linkobj/libc_pic.a \
@@ -674,6 +678,7 @@ $(common-objpfx)linkobj/libc.so: $(elf-objpfx)soinit.os \
                         $(elf-objpfx)ld.so \
                         $(shlib-lds)
        $(build-shlib)
+       $(call after-link,$@)
 
 ifeq ($(build-shared),yes)
 $(common-objpfx)libc.so: $(common-objpfx)libc.map

diff --git a/elf/Makefile b/elf/Makefile
index f2d1781..b43b48e 100644 (file)
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -349,6 +349,7 @@ $(objpfx)ld.so: $(objpfx)librtld.os $(ld-map)
                  $(filter-out $(map-file),$^) $(load-map-file)         \
                  -Wl,-soname=$(rtld-installed-name)                    \
                  -Wl,-defsym=_begin=0
+       $(call after-link,$@.new)
        $(READELF) -s $@.new \
          | $(AWK) '($$7 ~ /^UND(|EF)$$/ && $$1 != "0:" && $$4 != "REGISTER") { print; p=1 } END { exit p != 0 }'
        mv -f $@.new $@