Partly based on:
- https://github.com/freebsd/freebsd-ports/blob/main/databases/firebird30-server/files/patch-builds-posix_Makefile.in.plugins_examples
- https://github.com/freebsd/freebsd-ports/blob/main/databases/firebird30-server/files/patch-extern_btyacc_Makefile
- https://github.com/freebsd/freebsd-ports/blob/main/databases/firebird30-server/files/patch-extern_cloop_Makefile
- https://github.com/freebsd/freebsd-ports/blob/main/databases/firebird30-server/files/patch-builds_posix_make.defaults
--- a/builds/posix/Makefile.in
+++ b/builds/posix/Makefile.in
@@ -688,8 +688,8 @@ install install-embedded silent_install package packages dist:
 # various cleaning
 #
 .PHONY: clean clean_objects clean_dependancies clean_extern_objects clean_build \
-		clean_gpre_gen clean_icu clean_dbs clean_examples clean_makefiles \
-		clean_editline clean_all
+		clean_gpre_gen clean_dbs clean_examples clean_makefiles \
+		clean_all
 
 
 clean: clean_objects clean_dependancies clean_extern_objects clean_build \
@@ -708,8 +708,6 @@ clean_config clean_all: clean clean_makefiles
 	$(RM) $(ROOT)/config.status
 	$(RM) $(ROOT)/libtool
 	$(RM_R) $(ROOT)/autom4te.cache
-	-$(MAKE) -C $(ROOT)/extern/editline distclean
-#	-$(MAKE) -C $(ROOT)/extern/icu/source distclean
 	-$(MAKE) -C $(ROOT)/extern/btyacc distclean
 
 clean_dbs:
@@ -724,12 +722,6 @@ clean_dbs:
 clean_examples:
 	$(RM) `find $(GEN_ROOT)/examples/ -type f ! -name 'Make*'`
 
-clean_editline:
-	-$(MAKE) -C $(ROOT)/extern/editline clean
-
-#clean_icu:
-#	-$(MAKE) -C $(ROOT)/extern/icu/source clean
-
 clean_tommath:
 	-$(MAKE) -C $(ROOT)/extern/libtommath clean
 
--- a/builds/posix/Makefile.in.plugins_examples
+++ b/builds/posix/Makefile.in.plugins_examples
@@ -99,7 +99,7 @@ AllObjects += $(CA_Objects)
 crypt_app: $(CRYPT_APP)
 
 $(CRYPT_APP):	$(CA_Objects)
-	$(EXE_LINK) $^ -o $@ $(FIREBIRD_LIBRARY_LINK)
+	$(EXE_LINK) $(LDFLAGS) $^ -o $@ $(FIREBIRD_LIBRARY_LINK)
 
 
 include $(ROOT)/gen/make.shared.targets
--- a/builds/posix/make.defaults
+++ b/builds/posix/make.defaults
@@ -240,7 +240,7 @@ LIBFBINTL_SO = $(FB_BUILD)/intl/$(LIB_PREFIX)fbintl.$(SHRLIB_EXT)
 
 ifeq ($(EDITLINE_FLG),Y)
   ifeq ($(STD_EDITLINE), true)
-	LIBEDITLINE := -l$(READLINE)
+	LIBEDITLINE := $(shell ${PKG_CONFIG} libedit --libs)
   else
 	LIBEDITLINE := $(LIB)/libedit.a
   endif
--- a/extern/btyacc/Makefile
+++ b/extern/btyacc/Makefile
@@ -42,7 +42,7 @@ OTHERS	      = README README.BYACC \
 all:		$(PROGRAM)
 
 $(PROGRAM):     $(OBJS) $(LIBS)
-		$(CC) $(LDFLAGS) -o $(PROGRAM) $(OBJS) $(LIBS)
+		$(CC) $(CFLAGS) $(LDFLAGS) -o $(PROGRAM) $(OBJS) $(LIBS)
 
 clean:;		rm -f $(OBJS)
 
--- a/extern/cloop/Makefile
+++ b/extern/cloop/Makefile
@@ -6,7 +6,7 @@ TARGET	:= release
 
 CC	:= $(CC)
 CXX	:= $(CXX)
-LD	:= $(CXX)
+LD	:= $(CXX) $(LDFLAGS)
 
 SRC_DIR		:= src
 BUILD_DIR	:= build
@@ -27,8 +27,10 @@ SRCS_CPP := $(foreach sdir,$(SRC_DIRS),$(wildcard $(sdir)/*.cpp))
 OBJS_C := $(patsubst $(SRC_DIR)/%.c,$(OBJ_DIR)/%.o,$(SRCS_C))
 OBJS_CPP := $(patsubst $(SRC_DIR)/%.cpp,$(OBJ_DIR)/%.o,$(SRCS_CPP))
 
-C_FLAGS := -ggdb -fPIC -MMD -MP -W -Wall -Wno-unused-parameter
-CXX_FLAGS := $(C_FLAGS)
+
+COMMON_C_FLAGS := -ggdb -fPIC -MMD -MP -W -Wall -Wno-unused-parameter
+C_FLAGS := $(COMMON_C_FLAGS) $(CFLAGS) $(CPPFLAGS)
+CXX_FLAGS := $(COMMON_C_FLAGS) $(CXXFLAGS) $(CPPFLAGS)
 FPC_FLAGS := -Mdelphi
 
 ifeq ($(TARGET),release)