gcc: write builtin specs before modifications (#43956)

1 files changed, 8 insertions, 9 deletions

diff --git a/var/spack/repos/builtin/packages/gcc/package.py b/var/spack/repos/builtin/packages/gcc/package.py
index 6d94e2785d..0ed2f2f3b8 100644
--- a/var/spack/repos/builtin/packages/gcc/package.py
+++ b/var/spack/repos/builtin/packages/gcc/package.py
@@ -980,17 +980,18 @@ class Gcc(AutotoolsPackage, GNUMirrorPackage):
 
         specs_file = join_path(self.spec_dir, "specs")
         with open(specs_file, "w") as f:
+            # can't extend the builtins without dumping them first
+            f.write(self.spec["gcc"].command("-dumpspecs", output=str, error=os.devnull).strip())
+
+            f.write("\n\n# Generated by Spack\n\n")
+
             # rpath
             if rpath_dir:
-                print("*link_libgcc:", file=f)
-                print(f"+ -rpath={rpath_dir}", file=f)
-                print(file=f)
+                f.write(f"*link_libgcc:\n+ -rpath={rpath_dir}\n\n")
 
             # programs search path
             if self.spec.satisfies("+binutils"):
-                print("*self_spec:", file=f)
-                print(f"+ -B{self.spec['binutils'].prefix.bin}", file=f)
-                print(file=f)
+                f.write(f"*self_spec:\n+ -B{self.spec['binutils'].prefix.bin}\n\n")
         set_install_permissions(specs_file)
         tty.info(f"Wrote new spec file to {specs_file}")
 
@@ -1210,6 +1211,4 @@ class Gcc(AutotoolsPackage, GNUMirrorPackage):
 
         if relocation_args:
             with open(specs_file, "a") as f:
-                print("*self_spec:", file=f)
-                print(f"+ {' '.join(relocation_args)}", file=f)
-                print(file=f)
+                f.write(f"*self_spec:\n+ {' '.join(relocation_args)}\n\n")