Sync gc/extconf_base.rb

Author: peterzhu2118

gc/extconf_base.rb

@@ -4,11 +4,49 @@
 
 srcdir = File.join(__dir__, "..")
 $INCFLAGS << " -I#{srcdir}"
-
 $CPPFLAGS << " -DBUILDING_MODULAR_GC"
 
 append_cflags("-fPIC")
 
+DTRACE_RULES = <<~MAKE
+
+  probes.stamp: $(GC_DTRACE_OBJS)
+  	$(Q) if test -f $@ -o -f $(GC_DTRACE_OBJ); then \
+  	  $(RM) $(GC_DTRACE_OBJS) $@; \
+  	  $(ECHO) rebuilding objects which were modified by "dtrace -G"; \
+  	  $(MAKE) $(GC_DTRACE_OBJS); \
+  	fi
+  	$(Q) touch $@
+
+  $(GC_DTRACE_OBJ): $(top_srcdir)/probes.d $(GC_DTRACE_REBUILD:yes=probes.stamp)
+  	$(ECHO) processing GC probes in object files
+  	$(Q) CC="$(CC)" CFLAGS="$(CFLAGS) $(INCFLAGS) $(CPPFLAGS)" $(GC_DTRACE) -G -C $(INCFLAGS) -s $(top_srcdir)/probes.d -o $@ $(GC_DTRACE_OBJS)
+MAKE
+
 def create_gc_makefile(name, &block)
-  create_makefile("librubygc.#{name}", &block)
+  dtrace_obj = ENV.fetch("DTRACE_OBJ", "")
+  dtrace_enabled = (name == "default" && !dtrace_obj.empty?)
+
+  if name == "default"
+    $INCFLAGS << " -I$(topdir)"
+    $headers << "$(topdir)/probes.h"
+    $cleanfiles << "probes.stamp"
+  end
+
+  create_makefile("librubygc.#{name}") do |conf|
+    conf = block.call(conf) if block
+    next conf unless dtrace_enabled
+
+    gc_objs = $objs.join(" ")
+    conf = Array(conf).join.sub(/^OBJS = .*$/, "OBJS = #{gc_objs} #{dtrace_obj}")
+    conf + <<~MAKE
+
+    \tGC_DTRACE = #{ENV.fetch("DTRACE")}
+    \tGC_DTRACE_OBJ = #{dtrace_obj}
+    \tGC_DTRACE_OBJS = #{gc_objs}
+    \tGC_DTRACE_REBUILD = #{ENV.fetch("DTRACE_REBUILD", "")}
+    MAKE
+  end
+
+  File.write("Makefile", DTRACE_RULES, mode: "ab") if dtrace_enabled
 end