Merge pull request #639 from stilor/tweak-gcc-movelibs

When moving gcc libs, prefer the same directory as libc

3 files changed, 56 insertions, 3 deletions

diff --git a/config/debug/gdb.in.gdbserver b/config/debug/gdb.in.gdbserver
index 2f5576b..07e6e13 100644
--- a/config/debug/gdb.in.gdbserver
+++ b/config/debug/gdb.in.gdbserver
@@ -15,15 +15,30 @@ config GDB_GDBSERVER_HAS_IPA_LIB
     depends on GDB_7_2_or_later
     default y
 
+# gdbserver is then linked with "-static -Wl,--dynamic-list=..." which
 config GDB_GDBSERVER_STATIC
     bool
     prompt "Build a static gdbserver"
-    depends on CONFIGURE_has_static_link
-    default y
+    depends on EXPERIMENTAL
     help
       In case you have trouble with dynamic loading of shared libraries,
       you will find that a static gdbserver comes in handy.
 
+      However, it has been noticed at least on x86 that enabling this
+      option produces an invalid gdbserver binary. It is linked with
+      "-static -Wl,--dynamic-list=..." which
+      # (a) requests invalid program interpreter
+      # (b) crashes glibc/uClibc-ng and does not work with musl
+      # See https://sourceware.org/ml/libc-alpha/2017-03/msg00267.html
+
+      It is possible it would work with other architectures, hence it is
+      not completely removed. Use with care and report to the mailing list
+      if the resulting gdbserver works.
+
+      For further details, see:
+      https://sourceware.org/bugzilla/show_bug.cgi?id=19617
+      https://sourceware.org/bugzilla/show_bug.cgi?id=21086
+
 config GDB_GDBSERVER_BUILD_IPA_LIB
     bool
     prompt "Build the IPA library"
diff --git a/config/debug/gdb.in.native b/config/debug/gdb.in.native
index 915debd..8684c05 100644
--- a/config/debug/gdb.in.native
+++ b/config/debug/gdb.in.native
@@ -15,9 +15,24 @@ if GDB_NATIVE
 config GDB_NATIVE_STATIC
     bool
     prompt "Build a static native gdb"
-    depends on CONFIGURE_has_static_link
+    depends on EXPERIMENTAL
     help
       In case you have trouble with dynamic loading of shared libraries,
       you will find that a static gdb comes in handy.
 
+      However, it has been noticed at least on x86 that enabling this
+      option produces an invalid gdb binary. It is linked with
+      "-static -Wl,--dynamic-list=..." which
+      # (a) requests invalid program interpreter
+      # (b) crashes glibc/uClibc-ng and does not work with musl
+      # See https://sourceware.org/ml/libc-alpha/2017-03/msg00267.html
+
+      It is possible it would work with other architectures, hence it is
+      not completely removed. Use with care and report to the mailing list
+      if the resulting gdbserver works.
+
+      For further details, see:
+      https://sourceware.org/bugzilla/show_bug.cgi?id=19617
+      https://sourceware.org/bugzilla/show_bug.cgi?id=21086
+
 endif # GDB_NATIVE
diff --git a/config/target.in b/config/target.in
index a905b23..485c587 100644
--- a/config/target.in
+++ b/config/target.in
@@ -51,6 +51,29 @@ config MULTILIB
       NOTE: The multilib feature in crosstool-NG is not well-tested.
             Use at your own risk, and report success and/or failure.
 
+config DEMULTILIB
+    bool "Attempt to combine libraries into a single directory"
+    default y if !MULTILIB
+    depends on !MULTILIB || EXPERIMENTAL
+    help
+      Normally, Crosstool-NG installs the libraries into the directories
+      as the configure for these libraries determines appropriate. For
+      example, for AArch64 glibc wants to install the libraries into
+      /lib64 but the default dynamic linker path is /lib/ld-linux-aarch64.so.1
+      (which is installed as a symlink to ../lib64/ld-VER.so).
+
+      However, not all consumers of the toolchain can handle the libraries
+      residing in multiple directories. To appease them, crosstool-NG can
+      attempt to combine the libraries back into a single /lib directory and
+      create all other directories as symlinks to /lib. This requires all
+      the library names to be unique within each sysroot.
+
+      Note that GCC may also use separate sysroots for different multilibs.
+      Hence it may make sense to enable this option even for multilib toolchains.
+      However, separate roots are rare (any other architecture aside from
+      SuperH using them?) and hence not well tested in crosstool-NG; therefore,
+      this option is experimental when MULTILIB is enabled.
+
 #--------------------------------------
 config ARCH_SUPPORTS_BOTH_MMU
     bool