Update ab.

Author: davidgiven

build/ab.mk

@@ -114,5 +114,5 @@ $(OBJ)/build.ninja $(OBJ)/build.targets &:
 
 include $(OBJ)/build.targets
 .PHONY: $(ninja-targets)
-$(ninja-targets) &: $(OBJ)/build.ninja
+$(ninja-targets) : $(OBJ)/build.ninja
 	+$(hide) $(NINJA) -f $(OBJ)/build.ninja $@

build/c.py

@@ -429,7 +429,7 @@ def programimpl(
     simplerule(
         replaces=self,
         ins=cfiles + libs,
-        outs=[f"={self.localname}$(EXT)"],
+        outs=[f"={self.localname}{toolchain.EXE}"],
         deps=deps,
         label=label,
         commands=commands,

build/toolchain.py

@@ -1,5 +1,10 @@
+import platform
+
+_is_windows = (platform.system() == "Windows")
+
 class Toolchain:
     PREFIX = ""
+    EXE = ".exe" if _is_windows else ""
 
 
 class HostToolchain(Toolchain):