Avoid unnecessary inclusion of strings.h

ir/common/debugger.c

@@ -18,15 +18,13 @@
 
 #include "debugger.h"
 
-#include <stdlib.h>
-#include <stdio.h>
+#include <ctype.h>
 #include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
-#include <strings.h>
 #include <time.h>
 
-#include <ctype.h>
-
 #include "set.h"
 #include "ident.h"
 #include "irhooks.h"
@@ -843,6 +841,22 @@ static void get_text(void)
 	lexer.len = len;
 }
 
+/**
+ * Simple custom strncasecmp variant to avoid posix strings.h inclusion.
+ */
+static bool firm_strncaseequal(const char *str0, const char *str1, size_t len)
+{
+	for (size_t i = 0; i < len; ++i) {
+		unsigned char const c0 = str0[i];
+		unsigned char const c1 = str1[i];
+		if (toupper(c0) != toupper(c1))
+			return false;
+		if (c0 == '\0')
+			break;
+	}
+	return true;
+}
+
 /**
  * The lexer.
  */
@@ -868,7 +882,7 @@ static unsigned get_token(void)
 			--len;
 		}
 		for (size_t i = ARRAY_SIZE(reserved); i-- != 0;) {
-			if (strncasecmp(tok_start, reserved[i], len) == 0
+			if (firm_strncaseequal(tok_start, reserved[i], len)
 			    && reserved[i][len] == '\0')
 				return first_token + i;
 		}

ir/tv/tv.c

@@ -21,7 +21,6 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdlib.h>
-#include <strings.h>
 
 #include "bitfiddle.h"
 #include "hashptr.h"