diff --git a/src/CHANGELOG b/src/CHANGELOG
index cc7099fa5..ead274d08 100755
--- a/src/CHANGELOG
+++ b/src/CHANGELOG
@@ -49,6 +49,11 @@ ECL 10.1.1:
 
  - ECL now ships with ASDF version 1.596
 
+ - The variables C:*USER-CC-FLAGS* and C:*USER-LD-FLAGS* are lists of strings
+   which can be customized by the user to change the behavior of the C compiler
+   and the linker. Note, however, that the flags that ECL uses may take
+   priority.
+
 ;;; Local Variables: ***
 ;;; mode:text ***
 ;;; fill-column:79 ***
diff --git a/src/cmp/cmpdefs.lsp b/src/cmp/cmpdefs.lsp
index afa56fb1a..1d4aeeacd 100644
--- a/src/cmp/cmpdefs.lsp
+++ b/src/cmp/cmpdefs.lsp
@@ -23,6 +23,8 @@
 	   "*COMPILE-VERBOSE*"
 	   "*CC*"
 	   "*CC-OPTIMIZE*"
+           "*USER-CC-FLAGS*"
+           "*USER-LD-FLAGS*"
 	   "BUILD-ECL"
 	   "BUILD-PROGRAM"
            "BUILD-FASL"
@@ -453,11 +455,11 @@ coprocessor).")
 (defvar *cc-optimize* #-msvc "-O"
                       #+msvc "@CFLAGS_OPTIMIZE@")
 
-(defvar *ld-format* #-msvc "~A -o ~S -L~S ~{~S ~} ~@[~S~] ~A"
-                    #+msvc "~A -Fe~S~* ~{~S ~} ~@[~S~] ~A")
+(defvar *ld-format* #-msvc "~A -o ~S -L~S ~{~S ~} ~@[~S~]~{ '~A'~} ~A"
+                    #+msvc "~A -Fe~S~* ~{~S ~} ~@[~S~]~{ '~A'~} ~A")
 
-(defvar *cc-format* #-msvc "~A \"-I~A\" ~A ~:[~*~;~A~] -w -c \"~A\" -o \"~A\""
-                    #+msvc "~A -I\"~A\" ~A ~:[~*~;~A~] -w -c \"~A\" -Fo\"~A\"")
+(defvar *cc-format* #-msvc "~A \"-I~A\" ~A ~:[~*~;~A~] -w -c \"~A\" -o \"~A\"~{ '~A'~}"
+                    #+msvc "~A -I\"~A\" ~A ~:[~*~;~A~] -w -c \"~A\" -Fo\"~A\"~{ '~A'~}")
 
 #-dlopen
 (defvar *ld-flags* "@LDFLAGS@ -lecl @CORE_LIBS@ @FASL_LIBS@ @LIBS@")
@@ -471,6 +473,16 @@ coprocessor).")
 (defvar *ld-bundle-flags* #-msvc "@BUNDLE_LDFLAGS@ @LDFLAGS@ -lecl @FASL_LIBS@ @LIBS@"
                           #+msvc "@BUNDLE_LDFLAGS@ @LDFLAGS@ ecl.lib @CLIBS@")
 
+(defvar *user-ld-flags* '()
+"Flags and options to be passed to the linker when building FASL, shared libraries
+and standalone programs. It is not required to surround values with quotes or use
+slashes before special characters.")
+
+(defvar *user-cc-flags* '()
+"Flags and options to be passed to the C compiler when building FASL, shared libraries
+and standalone programs. It is not required to surround values with quotes or use
+slashes before special characters.")
+
 (defvar +shared-library-prefix+ "@SHAREDPREFIX@")
 (defvar +shared-library-extension+ "@SHAREDEXT@")
 (defvar +shared-library-format+ "@SHAREDPREFIX@~a.@SHAREDEXT@")
diff --git a/src/cmp/cmpmain.lsp b/src/cmp/cmpmain.lsp
index 83888ba8f..6b99d1c88 100755
--- a/src/cmp/cmpmain.lsp
+++ b/src/cmp/cmpmain.lsp
@@ -116,6 +116,7 @@ the environment variable TMPDIR to a different value." template)))
 	   (fix-for-mingw (ecl-library-directory))
 	   options
            *ld-rpath*
+           *user-ld-flags*
 	   *ld-flags*))
   #+msvc
   (embed-manifest-file o-pathname :program)
@@ -146,6 +147,7 @@ the environment variable TMPDIR to a different value." template)))
 	   (fix-for-mingw (ecl-library-directory))
 	   options
            *ld-rpath*
+           *user-ld-flags*
 	   (dll-extra-flags o-pathname)))
   #+msvc
   (embed-manifest-file o-pathname :dll)
@@ -155,11 +157,12 @@ the environment variable TMPDIR to a different value." template)))
   (let ((lib-file (compile-file-pathname o-pathname :type :lib)))
     (safe-system
      (format nil
-	     "gcc -shared -o ~S -L~S ~{~S ~} ~@[~S~] ~@?"
+	     "gcc -shared -o ~S -L~S ~{~S ~} ~@[~S~]~{ '~A'~} ~@?"
 	     (si::coerce-to-filename o-pathname)
 	     (fix-for-mingw (ecl-library-directory))
 	     options
              *ld-rpath*
+             *user-ld-flags*
 	     *ld-shared-flags*))))
 
 #+dlopen
@@ -188,6 +191,7 @@ the environment variable TMPDIR to a different value." template)))
 	   (fix-for-mingw (ecl-library-directory))
 	   options
            *ld-rpath*
+           *user-ld-flags*
 	   (bundle-extra-flags init-name o-pathname)))
   #+msvc
   (embed-manifest-file o-pathname :fasl)
@@ -196,11 +200,12 @@ the environment variable TMPDIR to a different value." template)))
   #+(or mingw32)
   (safe-system
    (format nil
-	   "gcc -shared -o ~S -Wl,--export-all-symbols -L~S ~{~S ~} ~@[~S~] ~A"
+	   "gcc -shared -o ~S -Wl,--export-all-symbols -L~S ~{~S ~} ~@[~S~]~{ '~A'~} ~A"
 	   (si::coerce-to-filename o-pathname)
 	   (fix-for-mingw (ecl-library-directory))
 	   options
            *ld-rpath*
+           *user-ld-flags*
 	   *ld-bundle-flags*)))
 
 (defconstant +lisp-program-header+ "
@@ -922,7 +927,8 @@ from the C language code.  NIL means \"do not create the file\"."
            (fix-for-mingw (ecl-include-directory))
 	   *cc-flags* (>= (cmp-env-optimization 'speed) 2) *cc-optimize*
 	   (si::coerce-to-filename c-pathname)
-	   (si::coerce-to-filename o-pathname))
+	   (si::coerce-to-filename o-pathname)
+           *user-cc-flags*)
 ; Since the SUN4 assembler loops with big files, you might want to use this:
 ;   (format nil
 ;	   "~A ~@[~*-O1~] -S -I. -I~A -w ~A ; as -o ~A ~A"