[glibc/alistair/rv32.next] RISC-V: Add path of library directories for the 32-bit

[Alistair Francis <alistair23@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=08f88cc98ee77a7c7ad94107bc20bfaf3817a646

commit 08f88cc98ee77a7c7ad94107bc20bfaf3817a646
Author: Zong Li <zongbox@gmail.com>
Date:   Fri Nov 30 17:15:44 2018 +0800

    RISC-V: Add path of library directories for the 32-bit
    
    For the recommand of 64 bit version, we add the libraries path of 32 bit
    in this patch.
    
    The status of RV32 binaries under RV64 kernels is that the ISA
    optionally supports having different XLEN for user and supervisor modes,
    but AFAIK there's no silicon that implements this feature, and the Linux
    kernel doesn't support it yet.
    
    For the recommand of 64 bit version, we add the libraries path of 32 bit
    in this patch. This includes a fix to avoid an out of bound array check
    when building with GCC 8.2.

Diff:
---
 sysdeps/unix/sysv/linux/riscv/dl-cache.h | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/sysdeps/unix/sysv/linux/riscv/dl-cache.h b/sysdeps/unix/sysv/linux/riscv/dl-cache.h
index c297dfe84f..60fc172edb 100644
--- a/sysdeps/unix/sysv/linux/riscv/dl-cache.h
+++ b/sysdeps/unix/sysv/linux/riscv/dl-cache.h
@@ -34,6 +34,8 @@
    RISC-V, libraries can be found in paths ending in:
      - /lib64/lp64d
      - /lib64/lp64
+     - /lib32/ilp32d
+     - /lib32/ilp32
      - /lib (only ld.so)
    so this will add all of those paths.
 
@@ -49,9 +51,16 @@
   do							    		\
     {									\
       size_t len = strlen (dir);					\
-      char path[len + 9];						\
+      char path[len + 10];						\
       memcpy (path, dir, len + 1);					\
-      if (len >= 12 && ! memcmp(path + len - 12, "/lib64/lp64d", 12))	\
+      if (len >= 13 && ! memcmp(path + len - 13, "/lib32/ilp32d", 13))	\
+        {								\
+          len -= 9;							\
+	  path[len] = '\0';						\
+        }								\
+      if (len >= 12							\
+          && (! memcmp(path + len - 12, "/lib32/ilp32", 12)		\
+              || ! memcmp(path + len - 12, "/lib64/lp64d", 12)))	\
 	{								\
 	  len -= 8;							\
 	  path[len] = '\0';						\
@@ -64,6 +73,10 @@
       add_dir (path);							\
       if (len >= 4 && ! memcmp(path + len - 4, "/lib", 4))		\
 	{								\
+	  memcpy (path + len, "32/ilp32d", 10);				\
+	  add_dir (path);						\
+	  memcpy (path + len, "32/ilp32", 9);				\
+	  add_dir (path);						\
 	  memcpy (path + len, "64/lp64d", 9);				\
 	  add_dir (path);						\
 	  memcpy (path + len, "64/lp64", 8);				\