Search path environment variables for cross-compilers.  See the discussion
at <http://gcc.gnu.org/ml/gcc/2013-02/msg00124.html>.

Note: Touch 'C_INCLUDE_PATH' et al. rather than 'CPATH', as discussed
at <http://bugs.gnu.org/22186>.

diff --git a/gcc/gcc.c b/gcc/gcc.c
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -4474,7 +4474,7 @@ process_command (unsigned int decoded_options_count,
     }
 
   temp = env.get (LIBRARY_PATH_ENV);
-  if (temp && *cross_compile == '0')
+  if (temp)
     {
       const char *startp, *endp;
       char *nstore = (char *) alloca (strlen (temp) + 3);
diff --git a/gcc/incpath.c b/gcc/incpath.c
--- a/gcc/incpath.c
+++ b/gcc/incpath.c
@@ -472,8 +472,8 @@ register_include_chains (cpp_reader *pfile, const char *sysroot,
 			 int stdinc, int cxx_stdinc, int verbose)
 {
   static const char *const lang_env_vars[] =
-    { "C_INCLUDE_PATH", "CPLUS_INCLUDE_PATH",
-      "OBJC_INCLUDE_PATH", "OBJCPLUS_INCLUDE_PATH" };
+    { "CROSS_C_INCLUDE_PATH", "CROSS_CPLUS_INCLUDE_PATH",
+      "CROSS_OBJC_INCLUDE_PATH", "CROSS_OBJCPLUS_INCLUDE_PATH" };
   cpp_options *cpp_opts = cpp_get_options (pfile);
   size_t idx = (cpp_opts->objc ? 2: 0);
 
@@ -484,7 +484,7 @@ register_include_chains (cpp_reader *pfile, const char *sysroot,
 
   /* CPATH and language-dependent environment variables may add to the
      include chain.  */
-  add_env_var_paths ("CPATH", INC_BRACKET);
+  add_env_var_paths ("CROSS_CPATH", INC_BRACKET);
   add_env_var_paths (lang_env_vars[idx], INC_SYSTEM);
 
   target_c_incpath.extra_pre_includes (sysroot, iprefix, stdinc);
diff --git a/gcc/system.h b/gcc/system.h
--- a/gcc/system.h
+++ b/gcc/system.h
@@ -1244,4 +1244,6 @@ void gcc_stablesort (void *, size_t, size_t,
    of the number.  */
 #define PRsa(n) "%" #n PRIu64 "%c"
 
+#define LIBRARY_PATH_ENV "CROSS_LIBRARY_PATH"
+
 #endif /* ! GCC_SYSTEM_H */
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<tr><td><span title='2023-07-13 18:20:05 +0200'>2023-07-13</span></td><td><a href='/guix/commit/gnu/packages/patches/glibc-2.37-hurd-clock_t_centiseconds.patch?id=0dd293b4d9095137c9952e16ca951f887b7e7018'>gnu: Add libc-for-target and glibc/hurd.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/patches/glibc-2.37-hurd-clock_t_centiseconds.patch
* gnu/packages/patches/glibc-2.37-hurd-local-clock_gettime_MONOTONIC.patch
* gnu/packages/patches/glibc-2.37-versioned-locpath.patch: New patches.
* gnu/local.mk (dist_patch_DATA): Register them.

* gnu/packages/base.scm (glibc/hurd, libc-for-target): New variables.
(glibc/hurd-headers): Use glibc/hurd.
* gnu/packages/commencement.scm (glibc-final-with-bootstrap-bash)[outputs,
source, arguments]
(glibc-final)[source]: Use libc-for-target instead of glibc.
* gnu/packages/cross-base.scm (cross-libc/deprecated, cross-libc*): Use
libc-for-target.

This part fixes

    https://issues.guix.gnu.org/63641#25

* gnu/packages/commencement.scm (%final-inputs): Change to memoized lambda
taking "system".
* gnu/packages/commencement.scm (canonical-package): Likewise, and update
user, passing (%current-system).
(make-gcc-toolchain): Update user, passing (%current-system).
* gnu/packages/base.scm (%final-inputs): Likewise.
* guix/scripts/refresh.scm (options-&gt;update-specs): Likewise.
* guix/build-system/gnu.scm (standard-packages): Add optional "system"
parameter.
(lower): Update caller.

Co-authored-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
Co-authored-by: Janneke Nieuwenhuizen &lt;janneke@gnu.org&gt;
</span></span></td><td>Josselin Poiret</td></tr>