libdw: enable support only on i386 and amd64
authorSergei Trofimovich <slyfox@gentoo.org>
Fri, 4 Dec 2015 22:07:13 +0000 (22:07 +0000)
committerSergei Trofimovich <siarheit@google.com>
Fri, 4 Dec 2015 22:07:13 +0000 (22:07 +0000)
Summary:
Currently libdw requires per-arch implementation of
set_initial_registers() function.

Otherwise build fails with linkage error
(seen on sparc):

  rts/dist/build/libHSrts_thr-ghc7.11.20151129.so:
      undefined reference to `set_initial_registers'
  collect2: error: ld returned 1 exit status
  `gcc' failed in phase `Linker'. (Exit code: 1)
  make[1]: *** [ghc/stage2/build/tmp/ghc-stage2] Error 1

Converted link-time error to compile-time error,
added arch whitelist.

Signed-off-by: Sergei Trofimovich <siarheit@google.com>
Reviewers: austin, thomie, bgamari

Reviewed By: bgamari

Differential Revision: https://phabricator.haskell.org/D1567

mk/config.mk.in
rts/Libdw.c

index 967c751..d7cd05b 100644 (file)
@@ -371,9 +371,9 @@ UseSystemLibFFI=@UseSystemLibFFI@
 FFILibDir=@FFILibDir@
 FFIIncludeDir=@FFIIncludeDir@
 
-
-# Include support for DWARF unwinding
-GhcRtsWithLibdw = @HaveLibdw@
+# GHC needs arch-specific tweak at least in
+#     rts/Libdw.c:set_initial_registers()
+GhcRtsWithLibdw=$(strip $(if $(filter $(TargetArch_CPP),i386 x86_64),@HaveLibdw@,NO))
 
 ################################################################################
 #
index 1ef51b2..8c3c581 100644 (file)
@@ -299,8 +299,7 @@ static bool set_initial_registers(Dwfl_Thread *thread,
         );
     return dwfl_thread_state_registers(thread, 0, 17, regs);
 }
-#endif
-#ifdef i386_HOST_ARCH
+#elif defined(i386_HOST_ARCH)
 static bool set_initial_registers(Dwfl_Thread *thread,
                                   void *arg STG_UNUSED) {
     Dwarf_Word regs[9];
@@ -321,6 +320,8 @@ static bool set_initial_registers(Dwfl_Thread *thread,
         );
     return dwfl_thread_state_registers(thread, 0, 9, regs);
 }
+#else
+#    error "Please implement set_initial_registers() for your arch"
 #endif
 
 static const Dwfl_Thread_Callbacks thread_cbs = {