Add multiarch dirs to linker search path

By default, tcc search libraries in /lib and /usr/local/lib while crt*.o
files are searched in /usr/lib and ld.so is searched in /lib.
Unfortunetely the path are hardcoded in source code. This patch allow
tcc to look in an other directory and also to look in extra directories.
It's then possible to make tcc search libraries in /lib/x86_64-linux-gnu
and /usr/local/lib/x86_64-linux-gnu while crt*.o files are searched in
/usr/lib/x86_64-linux-gnu and ld.so is searched in
/lib/x86_64-linux-gnu.

3 files changed, 58 insertions, 21 deletions

diff --git a/configure b/configure
index d2049af..57317be 100755
--- a/configure
+++ b/configure
@@ -26,6 +26,8 @@ prefix=""
 execprefix=""
 bindir=""
 libdir=""
+lddir=""
+extralddir=""
 tccdir=""
 includedir=""
 mandir=""
@@ -108,6 +110,10 @@ for opt do
   ;;
   --libdir=*) libdir=`echo $opt | cut -d '=' -f 2`
   ;;
+  --lddir=*) lddir=`echo $opt | cut -d '=' -f 2`
+  ;;
+  --extralddir=*) extralddir="$extralddir:`echo $opt | cut -d '=' -f 2`"
+  ;;
   --includedir=*) includedir=`echo $opt | cut -d '=' -f 2`
   ;;
   --sharedir=*) sharedir=`echo $opt | cut -d '=' -f 2`
@@ -241,6 +247,8 @@ echo "  --exec-prefix=EPREFIX    install architecture-dependent files in EPREFIX
 echo "                           [same as prefix]"
 echo "  --bindir=DIR             user executables in DIR [EPREFIX/bin]"
 echo "  --libdir=DIR             object code libraries in DIR [EPREFIX/lib]"
+echo "  --lddir=DIR              loader library search path in DIR [/lib]"
+echo "  --extralddir=DIR         extra loader library search path in DIR []"
 echo "  --tccdir=DIR             installation directory [EPREFIX/lib/tcc]"
 echo "  --includedir=DIR         C header files in DIR [PREFIX/include]"
 echo "  --sharedir=DIR           documentation root DIR [PREFIX]/share"
@@ -322,21 +330,23 @@ if test x"$includedir" = x""; then
 includedir="${prefix}/include"
 fi
 
-echo "Binary  directory   $bindir"
-echo "TinyCC directory    $tccdir"
-echo "Library directory   $libdir"
-echo "Include directory   $includedir"
-echo "Manual directory    $mandir"
-echo "Info directory      $infodir"
-echo "Doc directory       $docdir"
-echo "Target root prefix  $sysroot"
-echo "Source path      $source_path"
-echo "C compiler       $cc"
-echo "CPU              $cpu"
-echo "Big Endian       $bigendian"
-echo "gprof enabled    $gprof"
-echo "cross compilers  $build_cross"
-echo "use libgcc       $use_libgcc"
+echo "Binary  directory                      $bindir"
+echo "TinyCC directory                       $tccdir"
+echo "Library directory                      $libdir"
+echo "Loader library search directory        ${lddir:-default value (see tcc.h)}"
+echo "Extra loader library search directory  ${extralddir:-(none)}"
+echo "Include directory                      $includedir"
+echo "Manual directory                       $mandir"
+echo "Info directory                         $infodir"
+echo "Doc directory                          $docdir"
+echo "Target root prefix                     $sysroot"
+echo "Source path                            $source_path"
+echo "C compiler                             $cc"
+echo "CPU                                    $cpu"
+echo "Big Endian                             $bigendian"
+echo "gprof enabled                          $gprof"
+echo "cross compilers                        $build_cross"
+echo "use libgcc                             $use_libgcc"
 
 echo "Creating config.mak and config.h"
 
@@ -356,6 +366,8 @@ echo "docdir=\$(DESTDIR)$docdir" >> config.mak
 echo "#define CONFIG_SYSROOT \"$sysroot\"" >> $TMPH
 echo "#ifndef CONFIG_TCCDIR" >> $TMPH
 echo "#define CONFIG_TCCDIR \"$tccdir\"" >> $TMPH
+echo "#define CONFIG_TCC_LDDIR \"$lddir\"" >> $TMPH
+echo "#define CONFIG_TCC_EXTRA_LDDIR \"$extralddir\"" >> $TMPH
 echo "#endif" >> $TMPH
 echo "CC=$cc" >> config.mak
 echo "GCC_MAJOR=$gcc_major" >> config.mak
diff --git a/libtcc.c b/libtcc.c
index f97336e..995e779 100644
--- a/libtcc.c
+++ b/libtcc.c
@@ -971,6 +971,30 @@ LIBTCCAPI TCCState *tcc_new(void)
     tcc_add_library_path(s, CONFIG_TCC_CRT_PREFIX);
     tcc_add_library_path(s, CONFIG_SYSROOT CONFIG_TCC_LDDIR);
     tcc_add_library_path(s, CONFIG_SYSROOT "/usr/local"CONFIG_TCC_LDDIR);
+#ifdef CONFIG_TCC_EXTRA_LDDIR
+    {
+        const char delim[] = ":";
+        char *tok, *tok_extra_libdir = NULL, *tok_save_ptr, *extra_libdir_str;
+        size_t toklen = 0, old_toklen = 0;
+
+        extra_libdir_str = tcc_strdup(CONFIG_TCC_EXTRA_LDDIR);
+        tok = strtok_r(extra_libdir_str, delim, &tok_save_ptr);
+        while (tok != NULL)
+        {
+            toklen = strlen(CONFIG_SYSROOT "/usr/local") + strlen(tok);
+            if (toklen > old_toklen)
+                tok_extra_libdir = tcc_realloc(tok_extra_libdir,
+                                               toklen * sizeof(char));
+            /* No need for snprintf: value in tok comes from tcc compilation */
+            sprintf(tok_extra_libdir, CONFIG_SYSROOT "%s", tok);
+            tcc_add_library_path(s, tok_extra_libdir);
+            sprintf(tok_extra_libdir, CONFIG_SYSROOT "/usr/local%s", tok);
+            tcc_add_library_path(s, tok_extra_libdir);
+            tok = strtok_r(NULL, delim, &tok_save_ptr);
+        }
+        tcc_free(tok_extra_libdir);
+    }
+#endif
 #endif
 
     /* no section zero */
diff --git a/tcc.h b/tcc.h
index fcbfadc..686b3c5 100644
--- a/tcc.h
+++ b/tcc.h
@@ -142,13 +142,14 @@ typedef int BOOL;
 /* path to find crt1.o, crti.o and crtn.o. Only needed when generating
    executables or dlls */
 
-#if defined(TCC_TARGET_X86_64_CENTOS)
-# define CONFIG_TCC_CRT_PREFIX CONFIG_SYSROOT "/usr/lib64"
-# define CONFIG_TCC_LDDIR "/lib64"
-#else
-# define CONFIG_TCC_CRT_PREFIX CONFIG_SYSROOT "/usr/lib"
-# define CONFIG_TCC_LDDIR "/lib"
+#ifndef CONFIG_TCC_LDDIR
+  #if defined(TCC_TARGET_X86_64_CENTOS)
+    #define CONFIG_TCC_LDDIR "/lib64"
+  #else
+    #define CONFIG_TCC_LDDIR "/lib"
+  #endif
 #endif
+#define CONFIG_TCC_CRT_PREFIX CONFIG_SYSROOT "/usr" CONFIG_TCC_LDDIR
 
 #define INCLUDE_STACK_SIZE  32
 #define IFDEF_STACK_SIZE    64