Makefile

.PHONY: hello/libtest.a.in hello/libtest.a

DTLIB32 = /OUT:$@ /DEF:`echo $@ | $(SED) 's|/lib|/|;s|\.a|.def|'`

SED ?= sed

hello/libtest.a: hello/libtest.a.in
        ./test.exe $(DTLIB32)

all: hello/libtest.a

output

$ make all
./test.exe "/OUT:hello/libtest.a "/DEF:`echo hello/libtest.a | sed 's|/lib|/|;s|\.a|.def|'`
Proggy arg[1] = /OUT:hello/libtest.a /DEF:hello/test.def

test.c

// Compile with mingw-w64 GCC as: gcc test.c -o test.exe
#include <stdio.h>

int main(int argc, char * argv[]) {
  int i;
  for (i = 1; i < argc; ++i) {
    printf("Proggy arg[%d] = %s\n", i, argv[i]);
  }
  return 0;
}