commit 6fade5a6044b7102758f4ca66c8715ebc12a6306
Author: Martin Liska <mliska@suse.cz>
Date:   Thu Oct 22 14:07:29 2020 +0200

    LTO: check that make command works
    
    gcc/ChangeLog:
    
            PR lto/97524
            * lto-wrapper.c (make_exists): New function.
            (run_gcc): Use it to check that make is present and working
            for parallel execution.

--- gcc/lto-wrapper.c
+++ gcc/lto-wrapper.c
@@ -1321,6 +1321,26 @@ jobserver_active_p (void)
 	  && is_valid_fd (wfd));
 }
 
+/* Test that a make command is present and working, return true if so.  */
+
+static bool
+make_exists (void)
+{
+  const char *make = "make";
+  char **make_argv = buildargv (getenv ("MAKE"));
+  if (make_argv)
+    make = make_argv[0];
+  const char *make_args[] = {make, "--version", NULL};
+
+  int exit_status = 0;
+  int err = 0;
+  const char *errmsg
+    = pex_one (PEX_SEARCH, make_args[0], CONST_CAST (char **, make_args),
+	       "make", NULL, NULL, &exit_status, &err);
+  freeargv (make_argv);
+  return errmsg == NULL && exit_status == 0 && err == 0;
+}
+
 /* Execute gcc. ARGC is the number of arguments. ARGV contains the arguments. */
 
 static void
@@ -1541,6 +1561,10 @@ run_gcc (unsigned argc, char *argv[])
       jobserver = 1;
     }
 
+  /* We need make working for a parallel execution.  */
+  if (parallel && !make_exists ())
+    parallel = 0;
+
   if (linker_output)
     {
       char *output_dir, *base, *name;