3 files changed, 6 insertions, 1 deletions
diff --git a/common.h b/common.h
index d363038..ce7d604 100644
--- a/common.h
+++ b/common.h
@@ -129,6 +129,7 @@ struct option {
    bool trigraph;
    bool nocolor;
    bool pie, pic;
+   bool werror;
    union {
       struct {
          bool p : 1, /* after parsing */
diff --git a/io.c b/io.c
index ab3499b..b2d4364 100644
--- a/io.c
+++ b/io.c
@@ -1072,8 +1072,9 @@ warn(const struct span *span, const char *fmt, ...)
 {
    va_list ap;
 
+   if (ccopt.werror) ++nerror;
    va_start(ap, fmt);
-   vdiag(span, DGWARN, fmt, ap);
+   vdiag(span, ccopt.werror ? DGERROR : DGWARN, fmt, ap);
    va_end(ap);
 }
 
diff --git a/main.c b/main.c
index c0016ed..3833d85 100644
--- a/main.c
+++ b/main.c
@@ -202,6 +202,9 @@ optparse(char **args)
          }
          /* TODO depfiles */
       } else if (*arg == 'W') {
+         if (!strcmp(arg+1, "error")) {
+            ccopt.werror = 1;
+         }
          /* TODO warning switches */
       } else Bad: warn(NULL, "unrecognized option: %'s", arg-1);
    }