Support `comp-enable-subr-trampolines' as string value

* src/comp.c (syms_of_comp): Update `comp-enable-subr-trampolines'.

* lisp/emacs-lisp/comp.el (native-comp-never-optimize-functions)
(comp--trampoline-abs-filename): Support
`comp-enable-subr-trampolines' string value.

* src/data.c (Ffset): Use Vcomp_enable_subr_trampolines now.

2 files changed, 5 insertions, 2 deletions

diff --git a/src/comp.c b/src/comp.c
index 7d67995fa87..82224845bff 100644
--- a/src/comp.c
+++ b/src/comp.c
@@ -5858,12 +5858,15 @@ The last directory of this list is assumed to be the system one.  */);
      dump reload.  */
   Vnative_comp_eln_load_path = Fcons (build_string ("../native-lisp/"), Qnil);
 
-  DEFVAR_BOOL ("comp-enable-subr-trampolines", comp_enable_subr_trampolines,
+  DEFVAR_LISP ("comp-enable-subr-trampolines", Vcomp_enable_subr_trampolines,
                doc: /* If non-nil, enable primitive trampoline synthesis.
 This makes Emacs respect redefinition or advises of primitive functions
 when they are called from Lisp code natively-compiled at `native-comp-speed'
 of 2.
 
+If `comp-enable-subr-trampolines' is a string it specifies a directory
+in which to deposit the trampoline.
+
 By default, this is enabled, and when Emacs sees a redefined or advised
 primitive called from natively-compiled Lisp, it generates a trampoline
 for it on-the-fly.
diff --git a/src/data.c b/src/data.c
index bb4d1347d72..a43fa8991fe 100644
--- a/src/data.c
+++ b/src/data.c
@@ -855,7 +855,7 @@ DEFUN ("fset", Ffset, Sfset, 2, 2, 0,
 #ifdef HAVE_NATIVE_COMP
   register Lisp_Object function = XSYMBOL (symbol)->u.s.function;
 
-  if (comp_enable_subr_trampolines
+  if (!NILP (Vcomp_enable_subr_trampolines)
       && SUBRP (function)
       && !SUBR_NATIVE_COMPILEDP (function))
     CALLN (Ffuncall, Qcomp_subr_trampoline_install, symbol);