diff -urN giac-1.9.0.orig/src/fenv.h giac-1.9.0/src/fenv.h
--- giac-1.9.0.orig/src/fenv.h	2021-03-20 12:09:36.000000000 +0100
+++ giac-1.9.0/src/fenv.h	1970-01-01 01:00:00.000000000 +0100
@@ -1,7 +0,0 @@
-#ifndef FENV_H
-#define FENV_H
-#define FE_TONEAREST 0
-#define FE_DOWNWARD 1
-#define FE_UPWARD 2
-#define PTHREAD_MUTEX_INITIALIZER 0
-#endif
diff -urN giac-1.9.0.orig/src/Makefile.am giac-1.9.0/src/Makefile.am
--- giac-1.9.0.orig/src/Makefile.am	2022-04-11 09:52:40.000000000 +0200
+++ giac-1.9.0/src/Makefile.am	2022-12-07 11:12:50.321144231 +0100
@@ -30,7 +30,7 @@
 lexer_tab_int.h \
 static_help.h giacPCH.h giacintl.h gmp_replacements.h myostream.h \
 lpsolve.h optimization.h signalprocessing.h graphe.h graphtheory.h nautywrapper.h markup.h kdisplay.h k_csdk.h k_defs.h \
-fenv.h libregexp.h libregexp-opcode.h libunicode.h libunicode-table.h \
+libregexp.h libregexp-opcode.h libunicode.h libunicode-table.h \
 libbf.h list.h cutils.h qjsgiac.h \
 quickjs.h js.h quickjs-atom.h quickjs-libc.h quickjs-opcode.h bf2gmp.h