Search the configured multilib

... before falling back to ld.so installation path (it is not the same -
gcc uses /lib/ld-uClibc-x86-64.so.0 for uClibc) or default /lib:/usr/lib.

This matches glibc behavior (see trusted-dirs.h generated during glibc
build).

Signed-off-by: Alexey Neyman <stilor@att.net>

ldso/ldso/Makefile.in

@@ -34,6 +34,11 @@ CFLAGS-$(DODEBUG)-ldso/ldso := -O2 -g
 
 CFLAGS-ldso.c := -DLDSO_ELFINTERP=\"$(TARGET_ARCH)/elfinterp.c\"
 
+# Search non-default multilib directories
+ifneq ($(MULTILIB_DIR),lib)
+CFLAGS-ldso.c	+= -DLDSO_MULTILIB_DIR=\"$(MULTILIB_DIR)\"
+endif
+
 ifeq ($(TARGET_ARCH),arc)
 CFLAGS-ldso.c += -mno-long-calls
 endif

ldso/ldso/dl-elf.c

@@ -307,6 +307,19 @@ struct elf_resolve *_dl_load_shared_library(unsigned int rflags, struct dyn_elf
 		}
 	}
 #endif
+
+#ifdef LDSO_MULTILIB_DIR
+	/* If multilib directory is selected, search it before falling back to
+	   standard lib directories. */
+	_dl_if_debug_dprint("\tsearching multilib lib path list\n");
+	tpnt1 = search_for_named_library(libname, rflags,
+					UCLIBC_RUNTIME_PREFIX LDSO_MULTILIB_DIR ":"
+					UCLIBC_RUNTIME_PREFIX "usr" LDSO_MULTILIB_DIR,
+					rpnt, NULL);
+	if (tpnt1 != NULL)
+		return tpnt1;
+#endif
+
 #if defined SHARED && defined __LDSO_SEARCH_INTERP_PATH__
 	/* Look for libraries wherever the shared library loader
 	 * was installed */
@@ -315,6 +328,7 @@ struct elf_resolve *_dl_load_shared_library(unsigned int rflags, struct dyn_elf
 	if (tpnt1 != NULL)
 		return tpnt1;
 #endif
+
 	/* Lastly, search the standard list of paths for the library.
 	   This list must exactly match the list in uClibc/ldso/util/ldd.c */
 	_dl_if_debug_dprint("\tsearching full lib path list\n");