t-linux64 (MULTILIB_OSDIRNAMES): Use ../lib32 as the multilib osdirname if it exists.

2007-09-27  Matthias Klose  <doko@ubuntu.com>

        * config/i386/t-linux64 (MULTILIB_OSDIRNAMES): Use ../lib32 as the
        multilib osdirname if it exists.
        * config/rs6000/t-linux64 (MULTILIB_OSDIRNAMES): Likewise.

From-SVN: r128845

gcc/ChangeLog

+2007-09-27  Matthias Klose  <doko@ubuntu.com>
+
+	* config/i386/t-linux64 (MULTILIB_OSDIRNAMES): Use ../lib32 as the
+	multilib osdirname if it exists.
+	* config/rs6000/t-linux64 (MULTILIB_OSDIRNAMES): Likewise.
+
 2007-09-27  Ian Lance Taylor  <iant@google.com>
 
 	PR tree-optimization/33565

gcc/config/i386/t-linux64

@@ -4,9 +4,16 @@
 SHLIB_MAPFILES = $(srcdir)/libgcc-std.ver \
 		 $(srcdir)/config/i386/libgcc-x86_64-glibc.ver
 
+# On Debian, Ubuntu and other derivitive distributions, the 32bit libraries
+# are found in /lib32 and /usr/lib32, /lib64 and /usr/lib64 are symlinks to
+# /lib and /usr/lib, while other distributions install libraries into /lib64
+# and /usr/lib64.  The LSB does not enforce the use of /lib64 and /usr/lib64,
+# it doesn't tell anything about the 32bit libraries on those systems.  Set
+# MULTILIB_OSDIRNAMES according to what is found on the target.
+
 MULTILIB_OPTIONS = m64/m32
 MULTILIB_DIRNAMES = 64 32 
-MULTILIB_OSDIRNAMES = ../lib64 ../lib
+MULTILIB_OSDIRNAMES = ../lib64 $(if $(wildcard $(shell echo $(SYSTEM_HEADER_DIR))/../../usr/lib32),../lib32,../lib)
 
 LIBGCC = stmp-multilib
 INSTALL_LIBGCC = install-multilib

gcc/config/rs6000/t-linux64

@@ -7,12 +7,19 @@ LIB2FUNCS_EXTRA := $(sort $(LIB2FUNCS_EXTRA))
 
 TARGET_LIBGCC2_CFLAGS += -mno-minimal-toc
 
+# On Debian, Ubuntu and other derivitive distributions, the 32bit libraries
+# are found in /lib32 and /usr/lib32, /lib64 and /usr/lib64 are symlinks to
+# /lib and /usr/lib, while other distributions install libraries into /lib64
+# and /usr/lib64.  The LSB does not enforce the use of /lib64 and /usr/lib64,
+# it doesn't tell anything about the 32bit libraries on those systems.  Set
+# MULTILIB_OSDIRNAMES according to what is found on the target.
+
 MULTILIB_OPTIONS        = m64/m32 msoft-float
 MULTILIB_DIRNAMES       = 64 32 nof
 MULTILIB_EXTRA_OPTS     = fPIC mstrict-align
 MULTILIB_EXCEPTIONS     = m64/msoft-float
 MULTILIB_EXCLUSIONS     = m64/!m32/msoft-float
-MULTILIB_OSDIRNAMES	= ../lib64 ../lib nof
+MULTILIB_OSDIRNAMES	= ../lib64 $(if $(wildcard $(shell echo $(SYSTEM_HEADER_DIR))/../../usr/lib32),../lib32,../lib) nof
 MULTILIB_MATCHES        = $(MULTILIB_MATCHES_FLOAT)
 
 softfp_wrap_start := '\#ifndef __powerpc64__'