Fixed CFLAGS=-Os ghci failure (bug #452442 by Jason Mours). Added weak symbol processing into ghci. Limit maximum parallel job count down to 4 workers (-j1 is too slow on mmodern boxes, but -j12 kills the build almost always). Does not eliminate failures completely, but reduces them significantly (bug #456386).

(Portage version: 2.2.0_alpha186/cvs/Linux x86_64, signed Manifest commit with key 611FF3AA)

3 files changed, 1211 insertions, 1 deletions

diff --git a/dev-lang/ghc/ChangeLog b/dev-lang/ghc/ChangeLog
index 1885244b56c0..f4fac98b08c4 100644
--- a/dev-lang/ghc/ChangeLog
+++ b/dev-lang/ghc/ChangeLog
@@ -1,6 +1,16 @@
 # ChangeLog for dev-lang/ghc
 # Copyright 1999-2013 Gentoo Foundation; Distributed under the GPL v2
-# $Header: /var/cvsroot/gentoo-x86/dev-lang/ghc/ChangeLog,v 1.244 2013/07/19 10:21:35 slyfox Exp $
+# $Header: /var/cvsroot/gentoo-x86/dev-lang/ghc/ChangeLog,v 1.245 2013/08/01 13:15:33 slyfox Exp $
+
+*ghc-7.6.3-r1 (01 Aug 2013)
+
+  01 Aug 2013; Sergei Trofimovich <slyfox@gentoo.org>
+  +files/ghc-7.6.3-trac-3333-weak-syms.patch, +ghc-7.6.3-r1.ebuild:
+  Fixed CFLAGS=-Os ghci failure (bug #452442 by Jason Mours). Added weak symbol
+  processing into ghci. Limit maximum parallel job count down to 4 workers (-j1
+  is too slow on mmodern boxes, but -j12 kills the build almost always). Does
+  not eliminate failures completely, but reduces them significantly (bug
+  #456386).
 
   19 Jul 2013; Sergei Trofimovich <slyfox@gentoo.org> ghc-7.6.3.ebuild:
   Fix building on systems where libdir differs from the one we have built GHC
diff --git a/dev-lang/ghc/files/ghc-7.6.3-trac-3333-weak-syms.patch b/dev-lang/ghc/files/ghc-7.6.3-trac-3333-weak-syms.patch
new file mode 100644
index 000000000000..c3184a68c1e7
--- /dev/null
+++ b/dev-lang/ghc/files/ghc-7.6.3-trac-3333-weak-syms.patch
@@ -0,0 +1,387 @@
+The patch set adds support for weak symbols to ghci.
+
+For gentoo it fixes nonworking ghci / template haskell
+for package base.
+
+Steps to reproduce:
+    1. CFLAGS=-Os emerge ghc
+    2. ghci -package base
+    Loading package base ... linking ... ghc: /usr/lib64/ghc-7.6.3/base-4.6.0.1/HSbase-4.6.0.1.o: unknown symbol `stat'
+
+When built with -O2 weak 'stat' resolved to '__xstat' and we don't see any errors.
+But on olwer optimization levels 'stat' remains.
+
+Patches-by: akio
+Gentoo-bug: http://bugs.gentoo.org/452442
+Upstream-bug: http://ghc.haskell.org/trac/ghc/ticket/3333
+
+From 500d57d3a18412c78cab5abc4d91f1564edc964d Mon Sep 17 00:00:00 2001
+From: Takano Akio <aljee@hyper.cx>
+Date: Sat, 29 Dec 2012 11:47:22 +0900
+Subject: [PATCH 1/3] Linker.c: remove stablehash, which is no longer used
+
+---
+ includes/rts/Linker.h |    3 ---
+ rts/Linker.c          |   31 ++-----------------------------
+ 2 files changed, 2 insertions(+), 32 deletions(-)
+
+diff --git a/includes/rts/Linker.h b/includes/rts/Linker.h
+index e900e85..d20ebc2 100644
+--- a/includes/rts/Linker.h
++++ b/includes/rts/Linker.h
+@@ -23,9 +23,6 @@ typedef char    pathchar;
+ /* initialize the object linker */
+ void initLinker( void );
+ 
+-/* insert a stable symbol in the hash table */
+-void insertStableSymbol(pathchar* obj_name, char* key, StgPtr data);
+-
+ /* insert a symbol in the hash table */
+ void insertSymbol(pathchar* obj_name, char* key, void* data);
+ 
+diff --git a/rts/Linker.c b/rts/Linker.c
+index fa1de89..513fe3f 100644
+--- a/rts/Linker.c
++++ b/rts/Linker.c
+@@ -30,1 +30,0 @@
+-#include "Stable.h"
+@@ -150,9 +149,6 @@ int dynamicByDefault = 0;
+ /* Hash table mapping symbol names to Symbol */
+ static /*Str*/HashTable *symhash;
+ 
+-/* Hash table mapping symbol names to StgStablePtr */
+-static /*Str*/HashTable *stablehash;
+-
+ /* List of currently loaded objects */
+ ObjectCode *objects = NULL;     /* initially empty */
+ 
+@@ -1126,1 +1126,0 @@ typedef struct _RtsSymbolVal {
+-      SymI_HasProto(insertStableSymbol)                 \
+@@ -1488,7 +1483,6 @@ initLinker( void )
+ #if defined(THREADED_RTS) && (defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO))
+     initMutex(&dl_mutex);
+ #endif
+-    stablehash = allocStrHashTable();
+     symhash = allocStrHashTable();
+ 
+     /* populate the symbol table with stuff from the RTS */
+@@ -1817,17 +1811,6 @@ error:
+ }
+ 
+ /* -----------------------------------------------------------------------------
+- * insert a stable symbol in the hash table
+- */
+-
+-void
+-insertStableSymbol(pathchar* obj_name, char* key, StgPtr p)
+-{
+-  ghciInsertStrHashTable(obj_name, stablehash, key, getStablePtr(p));
+-}
+-
+-
+-/* -----------------------------------------------------------------------------
+  * insert a symbol in the hash table
+  */
+ void
+@@ -4749,8 +4732,6 @@ do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
+ #ifdef i386_HOST_ARCH
+       Elf_Addr  value;
+ #endif
+-      StgStablePtr stablePtr;
+-      StgPtr stableVal;
+ #ifdef arm_HOST_ARCH
+       int is_target_thm=0, T=0;
+ #endif
+@@ -4773,16 +4754,8 @@ do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
+ 
+          } else {
+             symbol = strtab + sym.st_name;
+-            stablePtr = (StgStablePtr)lookupHashTable(stablehash, (StgWord)symbol);
+-            if (NULL == stablePtr) {
+-              /* No, so look up the name in our global table. */
+-              S_tmp = lookupSymbol( symbol );
+-              S = (Elf_Addr)S_tmp;
+-            } else {
+-              stableVal = deRefStablePtr( stablePtr );
+-              S_tmp = stableVal;
+-              S = (Elf_Addr)S_tmp;
+-            }
++            S_tmp = lookupSymbol( symbol );
++            S = (Elf_Addr)S_tmp;
+          }
+          if (!S) {
+             errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
+-- 
+1.7.9.5
+
+From 2e5e0f7a90dd390adc5ae5fb2a3bc6e879aa42d6 Mon Sep 17 00:00:00 2001
+From: Takano Akio <aljee@hyper.cx>
+Date: Sat, 29 Dec 2012 11:59:34 +0900
+Subject: [PATCH 2/3] ghci: add support for ELF weak symbols
+
+---
+ rts/Linker.c |  102 ++++++++++++++++++++++++++++++++++++++++++++--------------
+ 1 file changed, 78 insertions(+), 24 deletions(-)
+
+diff --git a/rts/Linker.c b/rts/Linker.c
+index 513fe3f..5105085 100644
+--- a/rts/Linker.c
++++ b/rts/Linker.c
+@@ -146,7 +146,13 @@ int dynamicByDefault = 1;
+ int dynamicByDefault = 0;
+ #endif
+ 
+-/* Hash table mapping symbol names to Symbol */
++typedef struct _RtsSymbolInfo {
++    void *value;
++    const ObjectCode *owner;
++    HsBool weak;
++} RtsSymbolInfo;
++
++/* Hash table mapping symbol names to RtsSymbolInfo */
+ static /*Str*/HashTable *symhash;
+ 
+ /* List of currently loaded objects */
+@@ -1415,15 +1421,31 @@ static RtsSymbolVal rtsSyms[] = {
+  * Insert symbols into hash tables, checking for duplicates.
+  */
+ 
+-static void ghciInsertStrHashTable ( pathchar* obj_name,
+-                                     HashTable *table,
+-                                     char* key,
+-                                     void *data
+-                                   )
++static void ghciInsertSymbolTable(
++   pathchar* obj_name,
++   HashTable *table,
++   char* key,
++   void *data,
++   HsBool weak,
++   ObjectCode *owner)
+ {
+-   if (lookupHashTable(table, (StgWord)key) == NULL)
++   RtsSymbolInfo *pinfo = lookupStrHashTable(table, key);
++   if (!pinfo) /* new entry */
++   {
++      pinfo = stgMallocBytes(sizeof (*pinfo), "ghciInsertToSymbolTable");
++      pinfo->value = data;
++      pinfo->owner = owner;
++      pinfo->weak = weak;
++      insertStrHashTable(table, key, pinfo);
++      return;
++   } else if ((!pinfo->weak || pinfo->value) && weak) {
++     return; /* duplicate weak symbol, throw it away */
++   } else if (pinfo->weak) /* weak symbol is in the table */
+    {
+-      insertStrHashTable(table, (StgWord)key, data);
++      /* override the weak definition with the non-weak one */
++      pinfo->value = data;
++      pinfo->owner = owner;
++      pinfo->weak = HS_BOOL_FALSE;
+       return;
+    }
+    debugBelch(
+@@ -1444,6 +1466,32 @@ static void ghciInsertStrHashTable ( pathchar* obj_name,
+    );
+    stg_exit(1);
+ }
++
++static HsBool ghciLookupSymbolTable(HashTable *table,
++    const char *key, void **result)
++{
++    RtsSymbolInfo *pinfo = lookupStrHashTable(table, key);
++    if (!pinfo) {
++        *result = NULL;
++        return HS_BOOL_FALSE;
++    }
++    if (pinfo->weak)
++        IF_DEBUG(linker, debugBelch("lookup: promoting %s\n", key));
++    /* Once it's looked up, it can no longer be overridden */
++    pinfo->weak = HS_BOOL_FALSE;
++
++    *result = pinfo->value;
++    return HS_BOOL_TRUE;
++}
++
++static void ghciRemoveSymbolTable(HashTable *table, const char *key,
++    ObjectCode *owner)
++{
++    RtsSymbolInfo *pinfo = lookupStrHashTable(table, key);
++    if (!pinfo || owner != pinfo->owner) return;
++    removeStrHashTable(table, key, NULL);
++    stgFree(pinfo);
++}
+ /* -----------------------------------------------------------------------------
+  * initialize the object linker
+  */
+@@ -1487,8 +1535,8 @@ initLinker( void )
+ 
+     /* populate the symbol table with stuff from the RTS */
+     for (sym = rtsSyms; sym->lbl != NULL; sym++) {
+-        ghciInsertStrHashTable(WSTR("(GHCi built-in symbols)"),
+-                               symhash, sym->lbl, sym->addr);
++        ghciInsertSymbolTable(WSTR("(GHCi built-in symbols)"),
++                               symhash, sym->lbl, sym->addr, HS_BOOL_FALSE, NULL);
+         IF_DEBUG(linker, debugBelch("initLinker: inserting rts symbol %s, %p\n", sym->lbl, sym->addr));
+     }
+ #   if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
+@@ -1816,7 +1864,7 @@ error:
+ void
+ insertSymbol(pathchar* obj_name, char* key, void* data)
+ {
+-  ghciInsertStrHashTable(obj_name, symhash, key, data);
++  ghciInsertSymbolTable(obj_name, symhash, key, data, HS_BOOL_FALSE, NULL);
+ }
+ 
+ /* -----------------------------------------------------------------------------
+@@ -1829,9 +1877,8 @@ lookupSymbol( char *lbl )
+     IF_DEBUG(linker, debugBelch("lookupSymbol: looking up %s\n", lbl));
+     initLinker() ;
+     ASSERT(symhash != NULL);
+-    val = lookupStrHashTable(symhash, lbl);
+ 
+-    if (val == NULL) {
++    if (!ghciLookupSymbolTable(symhash, lbl, &val)) {
+         IF_DEBUG(linker, debugBelch("lookupSymbol: symbol not found\n"));
+ #       if defined(OBJFORMAT_ELF)
+         return internal_dlsym(dl_prog_handle, lbl);
+@@ -1903,7 +1950,7 @@ void ghci_enquire ( char* addr )
+          if (sym == NULL) continue;
+          a = NULL;
+          if (a == NULL) {
+-            a = lookupStrHashTable(symhash, sym);
++            ghciLookupSymbolTable(symhash, sym, (void **)&a);
+          }
+          if (a == NULL) {
+              // debugBelch("ghci_enquire: can't find %s\n", sym);
+@@ -2715,7 +2762,7 @@ unloadObj( pathchar *path )
+                 int i;
+                 for (i = 0; i < oc->n_symbols; i++) {
+                    if (oc->symbols[i] != NULL) {
+-                       removeStrHashTable(symhash, oc->symbols[i], NULL);
++                       ghciRemoveSymbolTable(symhash, oc->symbols[i], oc);
+                    }
+                 }
+             }
+@@ -3802,7 +3849,8 @@ ocGetNames_PEi386 ( ObjectCode* oc )
+          ASSERT(i >= 0 && i < oc->n_symbols);
+          /* cstring_from_COFF_symbol_name always succeeds. */
+          oc->symbols[i] = (char*)sname;
+-         ghciInsertStrHashTable(oc->fileName, symhash, (char*)sname, addr);
++         ghciInsertSymbolTable(oc->fileName, symhash, (char*)sname, addr,
++            HS_BOOL_FALSE, oc);
+       } else {
+ #        if 0
+          debugBelch(
+@@ -4595,6 +4643,7 @@ ocGetNames_ELF ( ObjectCode* oc )
+       for (j = 0; j < nent; j++) {
+ 
+          char  isLocal = FALSE; /* avoids uninit-var warning */
++         HsBool isWeak = HS_BOOL_FALSE;
+          char* ad      = NULL;
+          char* nm      = strtab + stab[j].st_name;
+          int   secno   = stab[j].st_shndx;
+@@ -4615,6 +4664,7 @@ ocGetNames_ELF ( ObjectCode* oc )
+          else
+          if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL
+                 || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL
++                || ELF_ST_BIND(stab[j].st_info)==STB_WEAK
+               )
+               /* and not an undefined symbol */
+               && stab[j].st_shndx != SHN_UNDEF
+@@ -4638,7 +4688,8 @@ ocGetNames_ELF ( ObjectCode* oc )
+             ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value;
+             if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) {
+                isLocal = TRUE;
+-            } else {
++               isWeak = FALSE;
++            } else { /* STB_GLOBAL or STB_WEAK */
+ #ifdef ELF_FUNCTION_DESC
+                /* dlsym() and the initialisation table both give us function
+                 * descriptors, so to be consistent we store function descriptors
+@@ -4649,6 +4700,7 @@ ocGetNames_ELF ( ObjectCode* oc )
+                IF_DEBUG(linker,debugBelch( "addOTabName(GLOB): %10p  %s %s\n",
+                                       ad, oc->fileName, nm ));
+                isLocal = FALSE;
++               isWeak = (ELF_ST_BIND(stab[j].st_info)==STB_WEAK);
+             }
+          }
+ 
+@@ -4661,7 +4713,7 @@ ocGetNames_ELF ( ObjectCode* oc )
+             if (isLocal) {
+                /* Ignore entirely. */
+             } else {
+-               ghciInsertStrHashTable(oc->fileName, symhash, nm, ad);
++               ghciInsertSymbolTable(oc->fileName, symhash, nm, ad, isWeak, oc);
+             }
+          } else {
+             /* Skip. */
+@@ -6306,11 +6358,13 @@ ocGetNames_MachO(ObjectCode* oc)
+                     else
+                     {
+                             IF_DEBUG(linker, debugBelch("ocGetNames_MachO: inserting %s\n", nm));
+-                            ghciInsertStrHashTable(oc->fileName, symhash, nm,
++                            ghciInsertSymbolTable(oc->fileName, symhash, nm,
+                                                     image
+                                                     + sections[nlist[i].n_sect-1].offset
+                                                     - sections[nlist[i].n_sect-1].addr
+-                                                    + nlist[i].n_value);
++                                                    + nlist[i].n_value,
++                                                    HS_BOOL_FALSE,
++                                                    oc);
+                             oc->symbols[curSymbol++] = nm;
+                     }
+                 }
+@@ -6341,8 +6395,8 @@ ocGetNames_MachO(ObjectCode* oc)
+                 nlist[i].n_value = commonCounter;
+ 
+                 IF_DEBUG(linker, debugBelch("ocGetNames_MachO: inserting common symbol: %s\n", nm));
+-                ghciInsertStrHashTable(oc->fileName, symhash, nm,
+-                                       (void*)commonCounter);
++                ghciInsertSymbolTable(oc->fileName, symhash, nm,
++                                       (void*)commonCounter, HS_BOOL_FALSE, oc);
+                 oc->symbols[curSymbol++] = nm;
+ 
+                 commonCounter += sz;
+@@ -6466,7 +6520,7 @@ machoInitSymbolsWithoutUnderscore(void)
+ 
+ #undef SymI_NeedsProto
+ #define SymI_NeedsProto(x)  \
+-    ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, *p++);
++    ghciInsertSymbolTable("(GHCi built-in symbols)", symhash, #x, *p++, HS_BOOL_FALSE, NULL);
+ 
+     RTS_MACHO_NOUNDERLINE_SYMBOLS
+ 
+-- 
+1.7.9.5
+
+From 916d7713b34b529ae7ec24eaa836a4eaca7724fc Mon Sep 17 00:00:00 2001
+From: Takano Akio <aljee@hyper.cx>
+Date: Sun, 6 Jan 2013 17:51:19 +0900
+Subject: [PATCH 3/3] Linker.c: add dso_handle to the symbol table
+
+---
+ rts/Linker.c |    7 +++++++
+ 1 file changed, 7 insertions(+)
+
+diff --git a/rts/Linker.c b/rts/Linker.c
+index 5105085..0b2bf63 100644
+--- a/rts/Linker.c
++++ b/rts/Linker.c
+@@ -1542,6 +1542,13 @@ initLinker( void )
+ #   if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
+     machoInitSymbolsWithoutUnderscore();
+ #   endif
++    /* GCC defines a special symbol __dso_handle which is resolved to NULL if
++       referenced from a statically linked module. We need to mimic this, but
++       we cannot use NULL because we use it to mean nonexistent symbols. So we
++       use an arbitrary (hopefully unique) address here.
++    */
++    ghciInsertSymbolTable(WSTR("(GHCi special symbols)"),
++        symhash, "__dso_handle", (void *)0x12345687, HS_BOOL_FALSE, NULL);
+ 
+ #   if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
+ #   if defined(RTLD_DEFAULT)
+-- 
+1.7.9.5
+
diff --git a/dev-lang/ghc/ghc-7.6.3-r1.ebuild b/dev-lang/ghc/ghc-7.6.3-r1.ebuild
new file mode 100644
index 000000000000..b693c3524d36
--- /dev/null
+++ b/dev-lang/ghc/ghc-7.6.3-r1.ebuild
@@ -0,0 +1,813 @@
+# Copyright 1999-2013 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Header: /var/cvsroot/gentoo-x86/dev-lang/ghc/ghc-7.6.3-r1.ebuild,v 1.1 2013/08/01 13:15:33 slyfox Exp $
+
+# Brief explanation of the bootstrap logic:
+#
+# Previous ghc ebuilds have been split into two: ghc and ghc-bin,
+# where ghc-bin was primarily used for bootstrapping purposes.
+# From now on, these two ebuilds have been combined, with the
+# binary USE flag used to determine whether or not the pre-built
+# binary package should be emerged or whether ghc should be compiled
+# from source.  If the latter, then the relevant ghc-bin for the
+# arch in question will be used in the working directory to compile
+# ghc from source.
+#
+# This solution has the advantage of allowing us to retain the one
+# ebuild for both packages, and thus phase out virtual/ghc.
+
+# Note to users of hardened gcc-3.x:
+#
+# If you emerge ghc with hardened gcc it should work fine (because we
+# turn off the hardened features that would otherwise break ghc).
+# However, emerging ghc while using a vanilla gcc and then switching to
+# hardened gcc (using gcc-config) will leave you with a broken ghc. To
+# fix it you would need to either switch back to vanilla gcc or re-emerge
+# ghc (or ghc-bin). Note that also if you are using hardened gcc-3.x and
+# you switch to gcc-4.x that this will also break ghc and you'll need to
+# re-emerge ghc (or ghc-bin). People using vanilla gcc can switch between
+# gcc-3.x and 4.x with no problems.
+
+EAPI="5"
+
+# to make make a crosscompiler use crossdev and symlink ghc tree into
+# cross overlay. result would look like 'cross-sparc-unknown-linux-gnu/ghc'
+#
+# 'CTARGET' definition and 'is_crosscompile' are taken from 'toolchain.eclass'
+export CTARGET=${CTARGET:-${CHOST}}
+if [[ ${CTARGET} = ${CHOST} ]] ; then
+	if [[ ${CATEGORY/cross-} != ${CATEGORY} ]] ; then
+		export CTARGET=${CATEGORY/cross-}
+	fi
+fi
+
+inherit autotools bash-completion-r1 eutils flag-o-matic ghc-package
+inherit multilib multiprocessing pax-utils toolchain-funcs versionator
+
+DESCRIPTION="The Glasgow Haskell Compiler"
+HOMEPAGE="http://www.haskell.org/ghc/"
+
+# we don't have any binaries yet
+arch_binaries=""
+
+# sorted!
+arch_binaries="$arch_binaries alpha? ( http://code.haskell.org/~slyfox/ghc-alpha/ghc-bin-${PV}-alpha.tbz2 )"
+#arch_binaries="$arch_binaries arm? ( http://code.haskell.org/~slyfox/ghc-arm/ghc-bin-${PV}-arm.tbz2 )"
+arch_binaries="$arch_binaries amd64? ( http://code.haskell.org/~slyfox/ghc-amd64/ghc-bin-${PV}-amd64.tbz2 )"
+arch_binaries="$arch_binaries ia64?  ( http://code.haskell.org/~slyfox/ghc-ia64/ghc-bin-${PV}-ia64.tbz2 )"
+#arch_binaries="$arch_binaries ppc? ( http://code.haskell.org/~slyfox/ghc-ppc/ghc-bin-${PV}-ppc.tbz2 )"
+#arch_binaries="$arch_binaries ppc64? ( http://code.haskell.org/~slyfox/ghc-ppc64/ghc-bin-${PV}-ppc64.tbz2 )"
+#arch_binaries="$arch_binaries sparc? ( http://code.haskell.org/~slyfox/ghc-sparc/ghc-bin-${PV}-sparc.tbz2 )"
+arch_binaries="$arch_binaries x86? ( http://code.haskell.org/~slyfox/ghc-x86/ghc-bin-${PV}-x86.tbz2 )"
+
+# various ports:
+#arch_binaries="$arch_binaries x86-fbsd? ( http://code.haskell.org/~slyfox/ghc-x86-fbsd/ghc-bin-${PV}-x86-fbsd.tbz2 )"
+
+# 0 - yet
+yet_binary() {
+	case "${ARCH}" in
+		alpha) return 0 ;;
+		#arm)
+		#	ewarn "ARM binary is built on armv5tel-eabi toolchain. Use with caution."
+		#	return 0
+		#;;
+		amd64) return 0 ;;
+		ia64) return 0 ;;
+		#ppc) return 0 ;;
+		#ppc64) return 0 ;;
+		#sparc) return 0 ;;
+		x86) return 0 ;;
+		*) return 1 ;;
+	esac
+}
+
+SRC_URI="!binary? ( http://www.haskell.org/ghc/dist/${PV}/${P}-src.tar.bz2 )"
+[[ -n $arch_binaries ]] && SRC_URI+=" !ghcbootstrap? ( $arch_binaries )"
+LICENSE="BSD"
+SLOT="0/${PV}"
+KEYWORDS="~amd64 ~x86 ~amd64-linux ~x86-linux ~ppc-macos ~x86-macos ~sparc-solaris ~x86-solaris"
+IUSE="doc ghcbootstrap ghcmakebinary +gmp llvm"
+IUSE+=" binary" # don't forget about me later!
+IUSE+=" elibc_glibc" # system stuff
+
+RDEPEND="
+	!kernel_Darwin? ( >=sys-devel/gcc-2.95.3 )
+	kernel_linux? ( >=sys-devel/binutils-2.17 )
+	kernel_SunOS? ( >=sys-devel/binutils-2.17 )
+	>=dev-lang/perl-5.6.1
+	>=dev-libs/gmp-5
+	virtual/libffi
+	!<dev-haskell/haddock-2.4.2
+	sys-libs/ncurses[unicode]"
+# earlier versions than 2.4.2 of haddock only works with older ghc releases
+
+# force dependency on >=gmp-5, even if >=gmp-4.1 would be enough. this is due to
+# that we want the binaries to use the latest versioun available, and not to be
+# built against gmp-4
+
+# similar for glibc. we have bootstrapped binaries against glibc-2.14
+DEPEND="${RDEPEND}
+	ghcbootstrap? (		>=dev-haskell/alex-2.3
+						>=dev-haskell/happy-1.18
+				doc? (	app-text/docbook-xml-dtd:4.2
+				app-text/docbook-xml-dtd:4.5
+				app-text/docbook-xsl-stylesheets
+				>=dev-libs/libxslt-1.1.2 ) )
+	!ghcbootstrap? ( !prefix? ( elibc_glibc? ( >=sys-libs/glibc-2.15 ) ) )"
+
+PDEPEND="!ghcbootstrap? ( =app-admin/haskell-updater-1.2* )"
+PDEPEND="
+	${PDEPEND}
+	llvm? ( sys-devel/llvm )"
+
+# ia64 fails to return from STG GMP primitives (stage2 always SIGSEGVs)
+REQUIRED_USE="ia64? ( !gmp )"
+
+is_crosscompile() {
+	[[ ${CHOST} != ${CTARGET} ]]
+}
+
+append-ghc-cflags() {
+	local flag compile assemble link
+	for flag in $*; do
+		case ${flag} in
+			compile)	compile="yes";;
+			assemble)	assemble="yes";;
+			link)		link="yes";;
+			*)
+				[[ ${compile}  ]] && GHC_FLAGS="${GHC_FLAGS} -optc${flag}" CFLAGS="${CFLAGS} ${flag}"
+				[[ ${assemble} ]] && GHC_FLAGS="${GHC_FLAGS} -opta${flag}" CFLAGS="${CFLAGS} ${flag}"
+				[[ ${link}     ]] && GHC_FLAGS="${GHC_FLAGS} -optl${flag}" FILTERED_LDFLAGS="${FILTERED_LDFLAGS} ${flag}";;
+		esac
+	done
+}
+
+ghc_setup_cflags() {
+	if is_crosscompile; then
+		export CFLAGS=${GHC_CFLAGS-"-O2 -pipe"}
+		export LDFLAGS=${GHC_LDFLAGS-"-Wl,-O1"}
+		einfo "Crosscompiling mode:"
+		einfo "   CHOST:   ${CHOST}"
+		einfo "   CTARGET: ${CTARGET}"
+		einfo "   CFLAGS:  ${CFLAGS}"
+		einfo "   LDFLAGS: ${LDFLAGS}"
+		return
+	fi
+	# We need to be very careful with the CFLAGS we ask ghc to pass through to
+	# gcc. There are plenty of flags which will make gcc produce output that
+	# breaks ghc in various ways. The main ones we want to pass through are
+	# -mcpu / -march flags. These are important for arches like alpha & sparc.
+	# We also use these CFLAGS for building the C parts of ghc, ie the rts.
+	strip-flags
+	strip-unsupported-flags
+
+	GHC_FLAGS=""
+	for flag in ${CFLAGS}; do
+		case ${flag} in
+
+			# Ignore extra optimisation (ghc passes -O to gcc anyway)
+			# -O2 and above break on too many systems
+			-O*) ;;
+
+			# Arch and ABI flags are what we're really after
+			-m*) append-ghc-cflags compile assemble ${flag};;
+
+			# Sometimes it's handy to see backtrace of RTS
+			# to get an idea what happens there
+			-g*) append-ghc-cflags compile ${flag};;
+
+			# Ignore all other flags, including all -f* flags
+		esac
+	done
+
+	FILTERED_LDFLAGS=""
+	for flag in ${LDFLAGS}; do
+		case ${flag} in
+			# Pass the canary. we don't quite respect LDFLAGS, but we have an excuse!
+			"-Wl,--hash-style="*) append-ghc-cflags link ${flag};;
+
+			# Ignore all other flags
+		esac
+	done
+
+	# hardened-gcc needs to be disabled, because the mangler doesn't accept
+	# its output.
+	gcc-specs-pie && append-ghc-cflags compile link	-nopie
+	gcc-specs-ssp && append-ghc-cflags compile		-fno-stack-protector
+
+	# prevent from failind building unregisterised ghc:
+	# http://www.mail-archive.com/debian-bugs-dist@lists.debian.org/msg171602.html
+	use ppc64 && append-ghc-cflags compile -mminimal-toc
+	# fix the similar issue as ppc64 TOC on ia64. ia64 has limited size of small data
+	# currently ghc fails to build haddock
+	# http://osdir.com/ml/gnu.binutils.bugs/2004-10/msg00050.html
+	use ia64 && append-ghc-cflags compile -G0 -Os
+
+	# Unfortunately driver/split/ghc-split.lprl is dumb
+	# enough to preserve stack marking for each split object
+	# and it flags stack marking violation:
+	# * !WX --- --- usr/lib64/ghc-7.4.1/base-4.5.0.0/libHSbase-4.5.0.0.a:Fingerprint__1.o
+	# * !WX --- --- usr/lib64/ghc-7.4.1/base-4.5.0.0/libHSbase-4.5.0.0.a:Fingerprint__2.o
+	# * !WX --- --- usr/lib64/ghc-7.4.1/base-4.5.0.0/libHSbase-4.5.0.0.a:Fingerprint__3.o
+	case $($(tc-getAS) -v 2>&1 </dev/null) in
+		*"GNU Binutils"*) # GNU ld
+			append-ghc-cflags compile assemble -Wa,--noexecstack
+			;;
+	esac
+}
+
+# substitutes string $1 to $2 in files $3 $4 ...
+relocate_path() {
+	local from=$1
+	local   to=$2
+	shift 2
+	local file=
+	for file in "$@"
+	do
+		sed -i -e "s|$from|$to|g" \
+			"$file" || die "path relocation failed for '$file'"
+	done
+}
+
+# changes hardcoded ghc paths and updates package index
+# $1 - new absolute root path
+relocate_ghc() {
+	local to=$1
+
+	# libdir for prebuilt binary and for current system may mismatch
+	# It does for prefix installation for example: bug #476998
+	local bin_ghc_prefix=${WORKDIR}/usr
+	local bin_libpath=$(echo "${bin_ghc_prefix}"/lib*)
+	local bin_libdir=${bin_libpath#${bin_ghc_prefix}/}
+
+	# backup original script to use it later after relocation
+	local gp_back="${T}/ghc-pkg-${PV}-orig"
+	cp "${WORKDIR}/usr/bin/ghc-pkg-${PV}" "$gp_back" || die "unable to backup ghc-pkg wrapper"
+
+	if [[ ${bin_libdir} != $(get_libdir) ]]; then
+		einfo "Relocating '${bin_libdir}' to '$(get_libdir)' (bug #476998)"
+		# moving the dir itself is not strictly needed
+		# but then USE=binary would result in installing
+		# in '${bin_libdir}'
+		mv "${bin_ghc_prefix}/${bin_libdir}" "${bin_ghc_prefix}/$(get_libdir)" || die
+
+		relocate_path "/usr/${bin_libdir}" "/usr/$(get_libdir)" \
+			"${WORKDIR}/usr/bin/ghc-${PV}" \
+			"${WORKDIR}/usr/bin/ghci-${PV}" \
+			"${WORKDIR}/usr/bin/ghc-pkg-${PV}" \
+			"${WORKDIR}/usr/bin/hsc2hs" \
+			"${WORKDIR}/usr/bin/runghc-${PV}" \
+			"$gp_back" \
+			"${WORKDIR}/usr/$(get_libdir)/${P}/package.conf.d/"*
+	fi
+
+	# Relocate from /usr to ${EPREFIX}/usr
+	relocate_path "/usr" "${to}/usr" \
+		"${WORKDIR}/usr/bin/ghc-${PV}" \
+		"${WORKDIR}/usr/bin/ghci-${PV}" \
+		"${WORKDIR}/usr/bin/ghc-pkg-${PV}" \
+		"${WORKDIR}/usr/bin/hsc2hs" \
+		"${WORKDIR}/usr/bin/runghc-${PV}" \
+		"${WORKDIR}/usr/$(get_libdir)/${P}/package.conf.d/"*
+
+	# this one we will use to regenerate cache
+	# so it should point to current tree location
+	relocate_path "/usr" "${WORKDIR}/usr" "$gp_back"
+
+	if use prefix; then
+		# and insert LD_LIBRARY_PATH entry to EPREFIX dir tree
+		# TODO: add the same for darwin's CHOST and it's DYLD_
+		local new_ldpath='LD_LIBRARY_PATH="'${EPREFIX}/$(get_libdir):${EPREFIX}/usr/$(get_libdir)'${LD_LIBRARY_PATH:+:}${LD_LIBRARY_PATH}"\nexport LD_LIBRARY_PATH'
+		sed -i -e '2i'"$new_ldpath" \
+			"${WORKDIR}/usr/bin/ghc-${PV}" \
+			"${WORKDIR}/usr/bin/ghci-${PV}" \
+			"${WORKDIR}/usr/bin/ghc-pkg-${PV}" \
+			"${WORKDIR}/usr/bin/hsc2hs" \
+			"${WORKDIR}/usr/bin/runghc-${PV}" \
+			"$gp_back" \
+			|| die "Adding LD_LIBRARY_PATH for wrappers failed"
+	fi
+
+	# regenerate the binary package cache
+	"$gp_back" recache || die "failed to update cache after relocation"
+	rm "$gp_back"
+}
+
+pkg_setup() {
+	if use ghcbootstrap; then
+		ewarn "You requested ghc bootstrapping, this is usually only used"
+		ewarn "by Gentoo developers to make binary .tbz2 packages for"
+		ewarn "use with the ghc ebuild's USE=\"binary\" feature."
+		use binary && \
+			die "USE=\"ghcbootstrap binary\" is not a valid combination."
+		[[ -z $(type -P ghc) ]] && \
+			die "Could not find a ghc to bootstrap with."
+	else
+		if ! yet_binary; then
+			eerror "Please try emerging with USE=ghcbootstrap and report build"
+			eerror "sucess or failure to the haskell team (haskell@gentoo.org)"
+			die "No binary available for '${ARCH}' arch yet, USE=ghcbootstrap"
+		fi
+	fi
+}
+
+src_unpack() {
+	# Create the ${S} dir if we're using the binary version
+	use binary && mkdir "${S}"
+
+	# the Solaris and Darwin binaries from ghc (maeder) need to be
+	# unpacked separately, so prevent them from being unpacked
+	local ONLYA=${A}
+	case ${CHOST} in
+		*-darwin* | *-solaris*)  ONLYA=${P}-src.tar.bz2  ;;
+	esac
+	unpack ${ONLYA}
+}
+
+src_prepare() {
+	ghc_setup_cflags
+
+	if ! use ghcbootstrap && [[ ${CHOST} != *-darwin* && ${CHOST} != *-solaris* ]]; then
+		# Modify the wrapper script from the binary tarball to use GHC_FLAGS.
+		# See bug #313635.
+		sed -i -e "s|\"\$topdir\"|\"\$topdir\" ${GHC_FLAGS}|" \
+			"${WORKDIR}/usr/bin/ghc-${PV}"
+
+		# allow hardened users use vanilla binary to bootstrap ghc
+		# ghci uses mmap with rwx protection at it implements dynamic
+		# linking on it's own (bug #299709)
+		pax-mark -m "${WORKDIR}/usr/$(get_libdir)/${P}/ghc"
+	fi
+
+	if use binary; then
+		if use prefix; then
+			relocate_ghc "${EPREFIX}"
+		fi
+
+		# Move unpacked files to the expected place
+		mv "${WORKDIR}/usr" "${S}"
+	else
+		if ! use ghcbootstrap; then
+			case ${CHOST} in
+				*-darwin* | *-solaris*)
+				# UPDATE ME for ghc-7
+				mkdir "${WORKDIR}"/ghc-bin-installer || die
+				pushd "${WORKDIR}"/ghc-bin-installer > /dev/null || die
+				use sparc-solaris && unpack ghc-6.10.4-sparc-sun-solaris2.tar.bz2
+				use x86-solaris && unpack ghc-7.0.3-i386-unknown-solaris2.tar.bz2
+				use x86-macos && unpack ghc-7.4.1-i386-apple-darwin.tar.bz2
+				use x64-macos && unpack ghc-7.4.1-x86_64-apple-darwin.tar.bz2
+				popd > /dev/null
+
+				pushd "${WORKDIR}"/ghc-bin-installer/ghc-[67].?*.? > /dev/null || die
+				# fix the binaries so they run, on Solaris we need an
+				# LD_LIBRARY_PATH which has our prefix libdirs, on
+				# Darwin we need to replace the frameworks with our libs
+				# from the prefix fix before installation, because some
+				# of the tools are actually used during configure/make
+				if [[ ${CHOST} == *-solaris* ]] ; then
+					export LD_LIBRARY_PATH="${EPREFIX}/$(get_libdir):${EPREFIX}/usr/$(get_libdir):${LD_LIBRARY_PATH}"
+				elif [[ ${CHOST} == *-darwin* ]] ; then
+					local readline_framework=GNUreadline.framework/GNUreadline
+					local gmp_framework=/opt/local/lib/libgmp.10.dylib
+					local ncurses_file=/opt/local/lib/libncurses.5.dylib
+					for binary in $(scanmacho -BRE MH_EXECUTE -F '%F' .) ; do
+						install_name_tool -change \
+							${readline_framework} \
+							"${EPREFIX}"/lib/libreadline.dylib \
+							${binary} || die
+						install_name_tool -change \
+							${gmp_framework} \
+							"${EPREFIX}"/usr/lib/libgmp.dylib \
+							${binary} || die
+						install_name_tool -change \
+							${ncurses_file} \
+							"${EPREFIX}"/usr/lib/libncurses.dylib \
+							${binary} || die
+					done
+					# we don't do frameworks!
+					sed -i \
+						-e 's/\(frameworks = \)\["GMP"\]/\1[]/g' \
+						-e 's/\(extraLibraries = \)\["m"\]/\1["m","gmp"]/g' \
+						rts/package.conf.in || die
+				fi
+
+				# it is autoconf, but we really don't want to give it too
+				# much arguments, in fact we do the make in-place anyway
+				./configure --prefix="${WORKDIR}"/usr || die
+				make install || die
+				popd > /dev/null
+				;;
+				*)
+				relocate_ghc "${WORKDIR}"
+				;;
+			esac
+		fi
+
+		sed -i -e "s|\"\$topdir\"|\"\$topdir\" ${GHC_FLAGS}|" \
+			"${S}/ghc/ghc.wrapper"
+
+		cd "${S}" # otherwise epatch will break
+
+		epatch "${FILESDIR}/ghc-7.0.4-CHOST-prefix.patch"
+
+		# epatch "${FILESDIR}"/${PN}-7.0.4-darwin8.patch
+		# failed to apply. FIXME
+		#epatch "${FILESDIR}"/${PN}-6.12.3-mach-o-relocation-limit.patch
+
+		# epatch "${FILESDIR}"/${PN}-7.4-rc2-macos-prefix-respect-gcc.patch
+		# epatch "${FILESDIR}"/${PN}-7.2.1-freebsd-CHOST.patch
+
+		we_want_libffi_workaround() {
+			use ghcmakebinary && return 1
+
+			# pick only registerised arches
+			# http://bugs.gentoo.org/463814
+			use amd64 && return 0
+			use x86 && return 0
+			return 1
+		}
+		# one mode external depend with unstable ABI be careful to stash it
+		# avoid external libffi runtime when we build binaries
+		we_want_libffi_workaround && epatch "${FILESDIR}"/${PN}-7.5.20120505-system-libffi.patch
+
+		epatch "${FILESDIR}"/${PN}-7.4.1-ticket-7339-fix-unaligned-unreg.patch
+		epatch "${FILESDIR}"/${PN}-7.6.2-integer-simple-div-mod.patch
+		# ghc-7.8 changed linker code and likely fixed it
+		epatch "${FILESDIR}"/${PN}-7.6.3-trac-3333-weak-syms.patch
+
+		if use prefix; then
+			# Make configure find docbook-xsl-stylesheets from Prefix
+			sed -e '/^FP_DIR_DOCBOOK_XSL/s:\[.*\]:['"${EPREFIX}"'/usr/share/sgml/docbook/xsl-stylesheets/]:' \
+				-i utils/haddock/doc/configure.ac || die
+		fi
+
+		# as we have changed the build system
+		eautoreconf
+	fi
+}
+
+src_configure() {
+	GHC_PV=${PV} # overrided in live ebuilds
+
+	if ! use binary; then
+		# initialize build.mk
+		echo '# Gentoo changes' > mk/build.mk
+
+		# Put docs into the right place, ie /usr/share/doc/ghc-${PV}
+		echo "docdir = ${EPREFIX}/usr/share/doc/${P}" >> mk/build.mk
+		echo "htmldir = ${EPREFIX}/usr/share/doc/${P}" >> mk/build.mk
+
+		# We also need to use the GHC_FLAGS flags when building ghc itself
+		echo "SRC_HC_OPTS+=${GHC_FLAGS}" >> mk/build.mk
+		echo "SRC_CC_OPTS+=${CFLAGS}" >> mk/build.mk
+		echo "SRC_LD_OPTS+=${FILTERED_LDFLAGS}" >> mk/build.mk
+
+		# We can't depend on haddock except when bootstrapping when we
+		# must build docs and include them into the binary .tbz2 package
+		# app-text/dblatex is not in portage, can not build PDF or PS
+		if use ghcbootstrap && use doc; then
+			echo "BUILD_DOCBOOK_PDF  = NO"  >> mk/build.mk
+			echo "BUILD_DOCBOOK_PS   = NO"  >> mk/build.mk
+			echo "BUILD_DOCBOOK_HTML = YES" >> mk/build.mk
+			if is_crosscompile; then
+				# TODO this is a workaround for this build error with the live ebuild with haddock:
+				# make[1]: *** No rule to make target `compiler/stage2/build/Module.hi',
+				# needed by `utils/haddock/dist/build/Main.o'.  Stop.
+				echo "HADDOCK_DOCS       = NO" >> mk/build.mk
+			else
+				echo "HADDOCK_DOCS       = YES" >> mk/build.mk
+			fi
+		else
+			echo "BUILD_DOCBOOK_PDF  = NO" >> mk/build.mk
+			echo "BUILD_DOCBOOK_PS   = NO" >> mk/build.mk
+			echo "BUILD_DOCBOOK_HTML = NO" >> mk/build.mk
+			echo "HADDOCK_DOCS       = NO" >> mk/build.mk
+		fi
+
+		# circumvent a very strange bug that seems related with ghc producing
+		# too much output while being filtered through tee (e.g. due to
+		# portage logging) reported as bug #111183
+		echo "SRC_HC_OPTS+=-w" >> mk/build.mk
+
+		# some arches do not support ELF parsing for ghci module loading
+		# PPC64: never worked (should be easy to implement)
+		# alpha: never worked
+		# arm: http://hackage.haskell.org/trac/ghc/changeset/27302c9094909e04eb73f200d52d5e9370c34a8a
+		if use alpha || use ppc64; then
+			echo "GhcWithInterpreter=NO" >> mk/build.mk
+		fi
+
+		# we have to tell it to build unregisterised on some arches
+		# ppc64: EvilMangler currently does not understand some TOCs
+		# ia64: EvilMangler bitrot
+		# set GHC_IS_UNREG if you like to build slow unregisterised
+		# host compiler. Handy if you plan to user resulting
+		# host compiler as a booting compiler for crosscompiler
+		# which can work only in unregisterised mode.
+		if use alpha || use ia64 || use ppc64 || [[ -n ${GHC_IS_UNREG} ]]; then
+			echo "GhcUnregisterised=YES" >> mk/build.mk
+			echo "GhcWithNativeCodeGen=NO" >> mk/build.mk
+			echo "SplitObjs=NO" >> mk/build.mk
+			echo "GhcRTSWays := debug" >> mk/build.mk
+			echo "GhcNotThreaded=YES" >> mk/build.mk
+		fi
+
+		# arm: no EvilMangler support, no NCG support
+		if use arm; then
+			echo "GhcUnregisterised=YES" >> mk/build.mk
+			echo "GhcWithNativeCodeGen=NO" >> mk/build.mk
+		fi
+
+		# Have "ld -r --relax" problem with split-objs on sparc:
+		if use sparc; then
+			echo "SplitObjs=NO" >> mk/build.mk
+		fi
+
+		if ! use llvm; then
+			echo "GhcWithLlvmCodeGen=NO" >> mk/build.mk
+		fi
+
+		# allows overriding build flavours for libraries:
+		# v   - vanilla (static libs)
+		# p   - profiled
+		# dyn - shared libraries
+		# example: GHC_LIBRARY_WAYS="v dyn"
+		if [[ -n ${GHC_LIBRARY_WAYS} ]]; then
+			echo "GhcLibWays=${GHC_LIBRARY_WAYS}" >> mk/build.mk
+		fi
+
+		# Get ghc from the unpacked binary .tbz2
+		# except when bootstrapping we just pick ghc up off the path
+		if ! use ghcbootstrap; then
+			export PATH="${WORKDIR}/usr/bin:${PATH}"
+		fi
+
+		if use gmp; then
+			echo "INTEGER_LIBRARY=integer-gmp" >> mk/build.mk
+		else
+			echo "INTEGER_LIBRARY=integer-simple" >> mk/build.mk
+		fi
+
+		# Since GHC 6.12.2 the GHC wrappers store which GCC version GHC was
+		# compiled with, by saving the path to it. The purpose is to make sure
+		# that GHC will use the very same gcc version when it compiles haskell
+		# sources, as the extra-gcc-opts files contains extra gcc options which
+		# match only this GCC version.
+		# However, this is not required in Gentoo, as only modern GCCs are used
+		# (>4).
+		# Instead, this causes trouble when for example ccache is used during
+		# compilation, but we don't want the wrappers to point to ccache.
+		# Due to the above, we simply set GCC to be "gcc". When compiling ghc it
+		# might point to ccache, once installed it will point to the users
+		# regular gcc.
+
+		local econf_args=()
+
+		is_crosscompile || econf_args+=--with-gcc=${CHOST}-gcc
+
+		econf ${econf_args[@]} --enable-bootstrap-with-devel-snapshot \
+			|| die "econf failed"
+
+		[[ ${PV} == *9999* ]] && GHC_PV="$(grep 'S\[\"PACKAGE_VERSION\"\]' config.status | sed -e 's@^.*=\"\(.*\)\"@\1@')"
+		GHC_TPF="$(grep 'S\[\"TargetPlatformFull\"\]' config.status | sed -e 's@^.*=\"\(.*\)\"@\1@')"
+	fi # ! use binary
+}
+
+src_compile() {
+	if ! use binary; then
+		limit_jobs() {
+			local user_jobs=$(makeopts_jobs)
+			local max_nonbreaking_jobs=$1
+
+			[[ ${user_jobs} -le ${max_nonbreaking_jobs} ]] && return
+
+			if [[ -n ${I_DEMAND_MY_CORES_LOADED} ]]; then
+				ewarn "You have requested parallel build which is known to break."
+				ewarn "Please report all breakages upstream."
+				return
+			else
+				ewarn "Limiting MAKEOPTS -j${user_jobs} -> -j${max_nonbreaking_jobs} (bug #456386)"
+				user_jobs=${max_nonbreaking_jobs}
+			fi
+			echo -j${user_jobs}
+		}
+		# ghc massively parallel make: #409631, #409873
+		#   but let users screw it by setting 'I_DEMAND_MY_CORES_LOADED'
+		# 4 parallel jobs usually does not break
+		emake $(limit_jobs 4) all
+		emake all V=1
+
+		if is_crosscompile; then
+			# runghc does not work for a stage1 compiler, we can build it anyway
+			# so it will print the error message: not built for interactive use
+			pushd "${S}/utils/runghc" || die "Could not cd to utils/runghc"
+			if [ ! -f Setup.hs ]; then
+				echo 'import Distribution.Simple; main = defaultMainWithHooks defaultUserHooks' \
+					> Setup.hs || die "failed to create default Setup.hs"
+			fi
+			ghc -o setup --make Setup.hs || die "setup build failed"
+			./setup configure || die "runghc configure failed"
+			sed -e "s@VERSION@\"${GHC_PV}\"@" -i runghc.hs
+			./setup build || die "runghc build failed"
+			popd
+		fi
+	fi # ! use binary
+}
+
+ghc-needs-c_nonshared-for-interpreter-libs() {
+	local sample_test=${T}/c_nonshared-test.c
+	echo "int main() {} " > "${sample_test}" || die
+	$(tc-getCC) -o "${sample_test}".result "${sample_test}" \
+		-L"${ROOT}"/usr/$(get_libdir) -lc_nonshared
+}
+
+add-c_nonshared-to-ghci-libs() {
+	local ghci_lib
+	local nonshared_dir=${T}/libc_nonshared_objects
+
+	is_crosscompile && return
+	ghc-needs-c_nonshared-for-interpreter-libs || return
+
+	get-nonshared-objects() {
+		# ns - 'nonshared'
+		local ns_objects=" "
+		local ns_sym
+		local ns_srco
+		local ns_dsto
+
+		# extract
+		mkdir "${nonshared_dir}" || die
+		pushd "${nonshared_dir}" >/dev/null || die
+		$(tc-getAR) x "${ROOT}"/usr/$(get_libdir)/libc_nonshared.a
+		popd >/dev/null || die
+
+		for ns_sym in \
+			stat    fstat   lstat mknod \
+			stat64  fstat64 lstat64 \
+			fstatat fstatat64 mknodat
+		do
+			ns_srco=${nonshared_dir}/${ns_sym}.oS
+			ns_dsto=${nonshared_dir}/${ns_sym}_weakened.o
+			[[ -f ${ns_srco} ]] || continue
+			# here we do The Magic:
+			# 1. --keep-global-symbol= hides everything to adoid double definition
+			#    of stuff like __stat, __fstat and
+			# 2. --weaken converts exported symbols to weak symbols to be available
+			#    for redefinition
+			$(tc-getOBJCOPY) \
+				--weaken --keep-global-symbol=${ns_sym} \
+				"${ns_srco}" "${ns_dsto}" || die
+
+			ns_objects+=" ${ns_dsto}"
+		done
+
+		echo "${ns_objects}"
+	}
+	# bug #452442: when building libraries for ghci
+	# ghc basically glues them together:
+	#   $ ld -r -o result foo.o bar.o ...
+	# that way some symbols defined in libc_nonshared.a
+	# do not get included into final HS*.o files
+	# We piggyback on one of early loaded wired-in library
+	# loaded before 'base'.
+	while read ghci_lib
+	do
+		einfo "relinking '${ghci_lib}' with c_includes"
+		mv "${ghci_lib}" "${ghci_lib}".unrelinked.o || die
+		$(tc-getLD) -r -o "${ghci_lib}"  \
+			"${ghci_lib}".unrelinked.o \
+			$(get-nonshared-objects) || die
+		rm -r "${nonshared_dir}" || die
+		rm "${ghci_lib}".unrelinked.o || die
+	done < <(find "${ED}"/usr/$(get_libdir)/${P}/ -name 'HSghc-prim*.o')
+}
+
+src_install() {
+	if use binary; then
+		use prefix && mkdir -p "${ED}"
+		mv "${S}/usr" "${ED}"
+
+		# Remove the docs if not requested
+		if ! use doc; then
+			rm -rf "${ED}/usr/share/doc/${P}/*/" \
+				"${ED}/usr/share/doc/${P}/*.html" \
+				|| die "could not remove docs (P vs PF revision mismatch?)"
+		fi
+	else
+		local insttarget="install"
+
+		# We only built docs if we were bootstrapping, otherwise
+		# we copy them out of the unpacked binary .tbz2
+		if use doc && ! use ghcbootstrap; then
+			mkdir -p "${ED}/usr/share/doc"
+			mv "${WORKDIR}/usr/share/doc/${P}" "${ED}/usr/share/doc" \
+				|| die "failed to copy docs"
+		else
+			dodoc "${S}/README" "${S}/ANNOUNCE" "${S}/LICENSE" "${S}/VERSION"
+		fi
+
+		emake -j1 ${insttarget} \
+			DESTDIR="${D}" \
+			|| die "make ${insttarget} failed"
+
+		# remove wrapper and linker
+		rm -f "${ED}"/usr/bin/haddock*
+
+		add-c_nonshared-to-ghci-libs
+
+		# ghci uses mmap with rwx protection at it implements dynamic
+		# linking on it's own (bug #299709)
+		# so mark resulting binary
+		pax-mark -m "${ED}/usr/$(get_libdir)/${P}/ghc"
+
+		if [[ ! -f "${S}/VERSION" ]]; then
+			echo "${GHC_PV}" > "${S}/VERSION" \
+				|| die "Could not create file ${S}/VERSION"
+		fi
+		dobashcomp "${FILESDIR}/ghc-bash-completion"
+
+	fi
+
+	# path to the package.cache
+	local package_confdir="${ED}/usr/$(get_libdir)/${PN}-${GHC_PV}/package.conf.d"
+	PKGCACHE="${package_confdir}"/package.cache
+	# copy the package.conf.d, including timestamp, save it so we can help
+	# users that have a broken package.conf.d
+	cp -pR "${package_confdir}"{,.initial} || die "failed to backup intial package.conf.d"
+
+	# copy the package.conf, including timestamp, save it so we later can put it
+	# back before uninstalling, or when upgrading.
+	cp -p "${PKGCACHE}"{,.shipped} \
+		|| die "failed to copy package.conf.d/package.cache"
+}
+
+pkg_preinst() {
+	# have we got an earlier version of ghc installed?
+	if has_version "<${CATEGORY}/${PF}"; then
+		haskell_updater_warn="1"
+	fi
+}
+
+pkg_postinst() {
+	ghc-reregister
+
+	# path to the package.cache
+	PKGCACHE="${EROOT}/usr/$(get_libdir)/${P}/package.conf.d/package.cache"
+
+	# give the cache a new timestamp, it must be as recent as
+	# the package.conf.d directory.
+	touch "${PKGCACHE}"
+
+	if [[ "${haskell_updater_warn}" == "1" ]]; then
+		ewarn
+		ewarn "\e[1;31m************************************************************************\e[0m"
+		ewarn
+		ewarn "You have just upgraded from an older version of GHC."
+		ewarn "You may have to run"
+		ewarn "      'haskell-updater --upgrade'"
+		ewarn "to rebuild all ghc-based Haskell libraries."
+		ewarn
+		ewarn "\e[1;31m************************************************************************\e[0m"
+		ewarn
+	fi
+	if is_crosscompile; then
+		ewarn
+		ewarn "\e[1;31m************************************************************************\e[0m"
+		ewarn
+		ewarn "GHC built as a cross compiler.  The interpreter, ghci and runghc, do"
+		ewarn "not work for a cross compiler."
+		ewarn "For the ghci error: \"<command line>: not built for interactive use\" see:"
+		ewarn "http://www.haskell.org/haskellwiki/GHC:FAQ#When_I_try_to_start_ghci_.28probably_one_I_compiled_myself.29_it_says_ghc-5.02:_not_built_for_interactive_use"
+		ewarn
+		ewarn "\e[1;31m************************************************************************\e[0m"
+		ewarn
+	fi
+}
+
+pkg_prerm() {
+	# Be very careful here... Call order when upgrading is (according to PMS):
+	# * src_install for new package
+	# * pkg_preinst for new package
+	# * pkg_postinst for new package
+	# * pkg_prerm for the package being replaced
+	# * pkg_postrm for the package being replaced
+	# so you'll actually be touching the new packages files, not the one you
+	# uninstall, due to that or installation directory ${P} will be the same for
+	# both packages.
+
+	# Call order for reinstalling is (according to PMS):
+	# * src_install
+	# * pkg_preinst
+	# * pkg_prerm for the package being replaced
+	# * pkg_postrm for the package being replaced
+	# * pkg_postinst
+
+	# Overwrite the modified package.cache with a copy of the
+	# original one, so that it will be removed during uninstall.
+
+	PKGCACHE="${EROOT}/usr/$(get_libdir)/${P}/package.conf.d/package.cache"
+	rm -rf "${PKGCACHE}"
+
+	cp -p "${PKGCACHE}"{.shipped,}
+}