[1/2] Add -print-lto-plugin

Message ID 1288376060-12168-1-git-send-email-andi@firstfloor.org
State New
Headers show

Commit Message

Andi Kleen Oct. 29, 2010, 6:14 p.m.
From: Andi Kleen <ak@linux.intel.com>

binutils have LTO linker plugin support now, but it requires hardcoding
the path to gcc's libexec dir in the Makefile. Add an option to the
gcc driver instead to print the full file name to avoid this.

This is especially useful for ar or nm.


2010-10-02  Andi Kleen <ak@linux.intel.com>

	* common.opt (-print-lto-plugin): Add.
	* doc/invoke.texi (-print-lto-plugin): Document.
	* gcc.c (display_help): Describe -print-lto-plugin.
	(main.c): Handle print_lto_plugin.
 gcc/common.opt      |    6 ++++++
 gcc/doc/invoke.texi |    9 ++++++++-
 gcc/gcc.c           |   13 +++++++++++++
 3 files changed, 27 insertions(+), 1 deletions(-)


diff --git a/gcc/common.opt b/gcc/common.opt
index a74d60d..2b6c73b 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -183,6 +183,9 @@  Driver JoinedOrMissing Alias(print-file-name=)
 Driver Alias(print-libgcc-file-name)
+Driver Alias(print-lto-plugin)
 Driver Alias(print-multi-directory)
@@ -1932,6 +1935,9 @@  Driver JoinedOrMissing Var(print_file_name)
+Driver Var(print_lto_plugin)
 Driver Var(print_multi_directory)
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 7ea042f..d6784ad 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -322,7 +322,7 @@  Objective-C and Objective-C++ Dialects}.
 -fdebug-prefix-map=@var{old}=@var{new} @gol
 -femit-struct-debug-baseonly -femit-struct-debug-reduced @gol
 -femit-struct-debug-detailed@r{[}=@var{spec-list}@r{]} @gol
--p  -pg  -print-file-name=@var{library}  -print-libgcc-file-name @gol
+-p  -pg  -print-file-name=@var{library}  -print-libgcc-file-name  -print-lto-plugin @gol
 -print-multi-directory  -print-multi-lib  -print-multi-os-directory @gol
 -print-prog-name=@var{program}  -print-search-dirs  -Q @gol
 -print-sysroot -print-sysroot-headers-suffix @gol
@@ -5725,6 +5725,13 @@  Same as @option{-print-file-name=libgcc.a}.
 This is useful when you use @option{-nostdlib} or @option{-nodefaultlibs}
 but you do want to link with @file{libgcc.a}.  You can do
+@item -print-lto-plugin
+@opindex print-lto-plugin
+Print the path name of the LTO linker plugin used by the compiler.
+This is useful to pass to ar, gold, ld or other binutils with linker 
+plugin support. 
 gcc -nostdlib @var{files}@dots{} `gcc -print-libgcc-file-name`
 @end smallexample
diff --git a/gcc/gcc.c b/gcc/gcc.c
index 13635d5..e6fc6d5 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -2928,6 +2928,7 @@  display_help (void)
   fputs (_("  -dumpmachine             Display the compiler's target processor\n"), stdout);
   fputs (_("  -print-search-dirs       Display the directories in the compiler's search path\n"), stdout);
   fputs (_("  -print-libgcc-file-name  Display the name of the compiler's companion library\n"), stdout);
+  fputs (_("  -print-lto-plugin        Display the name of the compiler's LTO plugin\n"), stdout);
   fputs (_("  -print-file-name=<lib>   Display the full path to library <lib>\n"), stdout);
   fputs (_("  -print-prog-name=<prog>  Display the full path to compiler component <prog>\n"), stdout);
   fputs (_("  -print-multi-directory   Display the root directory for versions of libgcc\n"), stdout);
@@ -3222,6 +3223,7 @@  driver_handle_option (struct gcc_options *opts,
     case OPT_print_sysroot:
     case OPT_print_multi_os_directory:
     case OPT_print_sysroot_headers_suffix:
+    case OPT_print_lto_plugin:
     case OPT_time:
     case OPT_wrapper:
       /* These options set the variables specified in common.opt
@@ -6536,6 +6538,17 @@  main (int argc, char **argv)
 	fatal_error ("not configured with sysroot headers suffix");
+  if (print_lto_plugin)
+    {
+      char *plugin;
+      plugin = find_a_file (&exec_prefixes, "liblto_plugin.so", R_OK, false);
+      if (!plugin)
+        fatal_error ("-print-lto-plugin specified, but no plugin found");    
+      printf ("%s\n", plugin);
+      return (0);
+    }
   if (print_help_list)
       display_help ();