Use generated DMD binary instead of src/dmd

auto-tester might run the testsuite with a different $(MODEL) than DMD
has been compiled with. Hence we manually check which binary exists to
infer the host model.

Author: wilzbach

test/Makefile

@@ -85,6 +85,7 @@ endif
 include ../src/osmodel.mak
 
 export OS
+BUILD=release
 
 ifeq (freebsd,$(OS))
     SHELL=/usr/local/bin/bash
@@ -100,31 +101,40 @@ export REQUIRED_ARGS=
 
 ifeq ($(findstring win,$(OS)),win)
 export ARGS=-inline -release -g -O
-export DMD=../src/dmd.exe
 export EXE=.exe
 export OBJ=.obj
 export DSEP=\\
 export SEP=$(subst /,\,/)
-
-DRUNTIME_PATH=..\..\druntime
-PHOBOS_PATH=..\..\phobos
-export DFLAGS=-I$(DRUNTIME_PATH)\import -I$(PHOBOS_PATH)
-export LIB=$(PHOBOS_PATH)
 else
 export ARGS=-inline -release -g -O -fPIC
-export DMD=../src/dmd
 export EXE=
 export OBJ=.o
 export DSEP=/
 export SEP=/
+endif
 
+# auto-tester might run the testsuite with a different $(MODEL) than DMD
+# has been compiled with. Hence we manually check which binary exists.
+ifeq (,$(wildcard ../generated/$(OS)/$(BUILD)/64/dmd$(EXE)))
+DMD_MODEL=32
+else
+DMD_MODEL=64
+endif
+export DMD=../generated/$(OS)/$(BUILD)/$(DMD_MODEL)/dmd$(EXE)
+
+ifeq ($(findstring win,$(OS)),win)
+DRUNTIME_PATH=..\..\druntime
+PHOBOS_PATH=..\..\phobos
+export DFLAGS=-I$(DRUNTIME_PATH)\import -I$(PHOBOS_PATH)
+export LIB=$(PHOBOS_PATH)
+else
 DRUNTIME_PATH=../../druntime
 PHOBOS_PATH=../../phobos
 # link against shared libraries (defaults to true on supported platforms, can be overridden w/ make SHARED=0)
 SHARED=$(if $(findstring $(OS),linux freebsd),1,)
-DFLAGS=-I$(DRUNTIME_PATH)/import -I$(PHOBOS_PATH) -L-L$(PHOBOS_PATH)/generated/$(OS)/release/$(MODEL)
+DFLAGS=-I$(DRUNTIME_PATH)/import -I$(PHOBOS_PATH) -L-L$(PHOBOS_PATH)/generated/$(OS)/$(BUILD)/$(MODEL)
 ifeq (1,$(SHARED))
-DFLAGS+=-defaultlib=libphobos2.so -L-rpath=$(PHOBOS_PATH)/generated/$(OS)/release/$(MODEL)
+DFLAGS+=-defaultlib=libphobos2.so -L-rpath=$(PHOBOS_PATH)/generated/$(OS)/$(BUILD)/$(MODEL)
 endif
 export DFLAGS
 endif