https://454200.bugs.gentoo.org/attachment.cgi?id=346650
http://sourceware.org/bugzilla/attachment.cgi?id=7008

We can now build an ld.so.cache of ARM shared objects on an x86 machine.

--- a/elf/cache.c
+++ b/elf/cache.c
@@ -100,6 +100,10 @@ print_entry (const char *lib, int flag, unsigned int osversion,
     case FLAG_AARCH64_LIB64:
       fputs (",AArch64", stdout);
       break;
+    /* Uses the ARM soft-float ABI.  */
+    case FLAG_ARM_LIBSF:
+      fputs (",soft-float", stdout);
+      break;
     case 0:
       break;
     default:

index 57a9a46..91190aa 100644
--- a/sysdeps/generic/ldconfig.h
+++ b/sysdeps/generic/ldconfig.h
@@ -36,6 +36,7 @@
 #define FLAG_X8664_LIBX32	0x0800
 #define FLAG_ARM_LIBHF		0x0900
 #define FLAG_AARCH64_LIB64	0x0a00
+#define FLAG_ARM_LIBSF		0x0b00
 
 /* Name of auxiliary cache.  */
 #define _PATH_LDCONFIG_AUX_CACHE "/var/cache/ldconfig/aux-cache"

--- a/ports/sysdeps/unix/sysv/linux/arm/dl-cache.h
+++ b/ports/sysdeps/unix/sysv/linux/arm/dl-cache.h
@@ -18,12 +18,17 @@
 
 #include <ldconfig.h>
 
+/* In order to support the transition from unmarked objects
+   to marked objects we must treat unmarked objects as
+   compatible with either FLAG_ARM_LIBHF or FLAG_ARM_LIBSF.  */
 #ifdef __ARM_PCS_VFP
 # define _dl_cache_check_flags(flags) \
-  ((flags) == (FLAG_ARM_LIBHF | FLAG_ELF_LIBC6))
+  ((flags) == (FLAG_ARM_LIBHF | FLAG_ELF_LIBC6) \
+   || (flags) == FLAG_ELF_LIBC6)
 #else
 # define _dl_cache_check_flags(flags) \
-  ((flags) == FLAG_ELF_LIBC6)
+  ((flags) == (FLAG_ARM_LIBSF | FLAG_ELF_LIBC6) \
+   || (flags) == FLAG_ELF_LIBC6)
 #endif
 
 #include_next <dl-cache.h>

--- a/ports/sysdeps/unix/sysv/linux/arm/readelflib.c
+++ b/ports/sysdeps/unix/sysv/linux/arm/readelflib.c
@@ -46,6 +46,12 @@ process_elf_file (const char *file_name, const char *lib, int *flag,
 	  if (elf32_header->e_flags & EF_ARM_ABI_FLOAT_HARD)
 	    *flag = FLAG_ARM_LIBHF|FLAG_ELF_LIBC6;
 	  else if (elf32_header->e_flags & EF_ARM_ABI_FLOAT_SOFT)
+	    *flag = FLAG_ARM_LIBSF|FLAG_ELF_LIBC6;
+	  else
+	    /* We must assume the unmarked objects are compatible
+	       with all ABI variants. Such objects may have been
+	       generated in a transitional period when the ABI
+	       tags were not added to all objects.  */
 	    *flag = FLAG_ELF_LIBC6;
 	}
     }