se->expr = build_call_array (rettype, fndecl, num_args, args);
}
+
+/* If bounds-checking is enabled, create code to verify at runtime that the
+ string lengths for both expressions are the same (needed for e.g. MERGE).
+ If bounds-checking is not enabled, does nothing. */
+
+static void
+conv_same_strlen_check (const char* intr_name, locus* where, tree a, tree b,
+ stmtblock_t* target)
+{
+ tree cond;
+ tree name;
+
+ /* If bounds-checking is disabled, do nothing. */
+ if (!flag_bounds_check)
+ return;
+
+ /* Compare the two string lengths. */
+ cond = fold_build2 (NE_EXPR, boolean_type_node, a, b);
+
+ /* Output the runtime-check. */
+ name = gfc_build_cstring_const (intr_name);
+ name = gfc_build_addr_expr (pchar_type_node, name);
+ gfc_trans_runtime_check (true, false, cond, target, where,
+ "Unequal character lengths (%ld/%ld) for arguments"
+ " to %s",
+ fold_convert (long_integer_type_node, a),
+ fold_convert (long_integer_type_node, b), name);
+}
+
+
/* The EXPONENT(s) intrinsic function is translated into
int ret;
frexp (s, &ret);
tree fsource;
tree mask;
tree type;
- tree len;
+ tree len, len2;
tree *args;
unsigned int num_args;
also have to set the string length for the result. */
len = args[0];
tsource = args[1];
+ len2 = args[2];
fsource = args[3];
mask = args[4];
+ conv_same_strlen_check ("MERGE", &expr->where, len, len2, &se->post);
+
se->string_length = len;
}
type = TREE_TYPE (tsource);
--- /dev/null
+! { dg-do run }
+! { dg-options "-fbounds-check" }
+! { dg-shouldfail "Unequal character lengths" }
+
+! PR fortran/38137
+! Test that -fbounds-check detects unequal character lengths to MERGE
+! at runtime.
+
+! Contributed by Tobias Burnus <burnus@gcc.gnu.org>
+
+subroutine foo(a)
+implicit none
+character(len=*) :: a
+character(len=3) :: b
+print *, merge(a,b,.true.) ! Unequal character lengths
+end subroutine foo
+
+call foo("ab")
+end