diff --git a/example/hello_world/hello.zig b/example/hello_world/hello.zig
index 93fa9ba8ae..31954f55e6 100644
--- a/example/hello_world/hello.zig
+++ b/example/hello_world/hello.zig
@@ -3,7 +3,6 @@ export executable "hello";
 use "std.zig";
 
 pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
-    // TODO implicit coercion from array to string
-    print_str("Hello, world!\n" as string);
+    print_str("Hello, world!\n");
     return 0;
 }
diff --git a/src/analyze.cpp b/src/analyze.cpp
index cba9f955ae..68b5719d87 100644
--- a/src/analyze.cpp
+++ b/src/analyze.cpp
@@ -618,7 +618,7 @@ static bool num_lit_fits_in_other_type(CodeGen *g, TypeTableEntry *literal_type,
     zig_unreachable();
 }
 
-static TypeTableEntry *resolve_type_compatibility(CodeGen *g, AstNode *node,
+static TypeTableEntry *resolve_type_compatibility(CodeGen *g, BlockContext *context, AstNode *node,
         TypeTableEntry *expected_type, TypeTableEntry *actual_type)
 {
     if (expected_type == nullptr)
@@ -642,8 +642,21 @@ static TypeTableEntry *resolve_type_compatibility(CodeGen *g, AstNode *node,
         expected_type->data.integral.is_signed == actual_type->data.integral.is_signed &&
         expected_type->size_in_bits > actual_type->size_in_bits)
     {
-        node->codegen_node->expr_node.cast_type = expected_type;
+        node->codegen_node->expr_node.implicit_cast.type = expected_type;
         node->codegen_node->expr_node.implicit_cast.op = CastOpIntWidenOrShorten;
+        node->codegen_node->expr_node.implicit_cast.source_node = node;
+        return expected_type;
+    }
+
+    // implicit constant sized array to string conversion
+    if (expected_type == g->builtin_types.entry_string &&
+        actual_type->id == TypeTableEntryIdArray &&
+        actual_type->data.array.child_type == g->builtin_types.entry_u8)
+    {
+        node->codegen_node->expr_node.implicit_cast.type = expected_type;
+        node->codegen_node->expr_node.implicit_cast.op = CastOpArrayToString;
+        node->codegen_node->expr_node.implicit_cast.source_node = node;
+        context->cast_expr_alloca_list.append(&node->codegen_node->expr_node.implicit_cast);
         return expected_type;
     }
 
@@ -655,7 +668,8 @@ static TypeTableEntry *resolve_type_compatibility(CodeGen *g, AstNode *node,
     return g->builtin_types.entry_invalid;
 }
 
-static TypeTableEntry *resolve_peer_type_compatibility(CodeGen *g, AstNode *parent_node,
+static TypeTableEntry *resolve_peer_type_compatibility(CodeGen *g, BlockContext *block_context,
+        AstNode *parent_node,
         AstNode *child1, AstNode *child2,
         TypeTableEntry *type1, TypeTableEntry *type2)
 {
@@ -668,8 +682,8 @@ static TypeTableEntry *resolve_peer_type_compatibility(CodeGen *g, AstNode *pare
         return parent_type;
     }
 
-    resolve_type_compatibility(g, child1, parent_type, type1);
-    resolve_type_compatibility(g, child2, parent_type, type2);
+    resolve_type_compatibility(g, block_context, child1, parent_type, type1);
+    resolve_type_compatibility(g, block_context, child2, parent_type, type2);
 
     return parent_type;
 }
@@ -874,6 +888,8 @@ static TypeTableEntry *analyze_cast_expr(CodeGen *g, ImportTableEntry *import, B
     }
 
     CastNode *cast_node = &node->codegen_node->data.cast_node;
+    cast_node->source_node = node;
+    cast_node->type = wanted_type;
 
     // special casing this for now, TODO think about casting and do a general solution
     if (wanted_type == g->builtin_types.entry_isize &&
@@ -891,7 +907,7 @@ static TypeTableEntry *analyze_cast_expr(CodeGen *g, ImportTableEntry *import, B
                 actual_type->data.array.child_type == g->builtin_types.entry_u8)
     {
         cast_node->op = CastOpArrayToString;
-        context->cast_expr_alloca_list.append(node);
+        context->cast_expr_alloca_list.append(cast_node);
         return wanted_type;
     } else if (actual_type->id == TypeTableEntryIdNumberLiteral &&
                num_lit_fits_in_other_type(g, actual_type, wanted_type))
@@ -1022,10 +1038,8 @@ static TypeTableEntry *analyze_bin_op_expr(CodeGen *g, ImportTableEntry *import,
             }
         case BinOpTypeBoolOr:
         case BinOpTypeBoolAnd:
-            analyze_expression(g, import, context, g->builtin_types.entry_bool,
-                    node->data.bin_op_expr.op1);
-            analyze_expression(g, import, context, g->builtin_types.entry_bool,
-                    node->data.bin_op_expr.op2);
+            analyze_expression(g, import, context, g->builtin_types.entry_bool, node->data.bin_op_expr.op1);
+            analyze_expression(g, import, context, g->builtin_types.entry_bool, node->data.bin_op_expr.op2);
             return g->builtin_types.entry_bool;
         case BinOpTypeCmpEq:
         case BinOpTypeCmpNotEq:
@@ -1188,8 +1202,8 @@ static VariableTableEntry *analyze_variable_declaration(CodeGen *g, ImportTableE
     return nullptr;
 }
 
-static TypeTableEntry *analyze_number_literal_expr(CodeGen *g, ImportTableEntry *import, BlockContext *context,
-        TypeTableEntry *expected_type, AstNode *node)
+static TypeTableEntry *analyze_number_literal_expr(CodeGen *g, ImportTableEntry *import,
+        BlockContext *block_context, TypeTableEntry *expected_type, AstNode *node)
 {
     TypeTableEntry *num_lit_type = g->num_lit_types[node->data.number_literal.kind];
     if (node->data.number_literal.overflow) {
@@ -1199,7 +1213,7 @@ static TypeTableEntry *analyze_number_literal_expr(CodeGen *g, ImportTableEntry
     } else if (expected_type) {
         NumberLiteralNode *codegen_num_lit = &node->codegen_node->data.num_lit_node;
         assert(!codegen_num_lit->resolved_type);
-        codegen_num_lit->resolved_type = resolve_type_compatibility(g, node, expected_type, num_lit_type);
+        codegen_num_lit->resolved_type = resolve_type_compatibility(g, block_context, node, expected_type, num_lit_type);
         return codegen_num_lit->resolved_type;
     } else {
         return num_lit_type;
@@ -1260,7 +1274,7 @@ static TypeTableEntry * analyze_expression(CodeGen *g, ImportTableEntry *import,
                         actual_return_type = g->builtin_types.entry_invalid;
                     }
 
-                    resolve_type_compatibility(g, node, expected_return_type, actual_return_type);
+                    resolve_type_compatibility(g, context, node, expected_return_type, actual_return_type);
                 } else {
                     add_node_error(g, node, buf_sprintf("return expression outside function definition"));
                 }
@@ -1453,14 +1467,14 @@ static TypeTableEntry * analyze_expression(CodeGen *g, ImportTableEntry *import,
                     else_type = analyze_expression(g, import, context, expected_type, node->data.if_expr.else_node);
                 } else {
                     else_type = g->builtin_types.entry_void;
-                    else_type = resolve_type_compatibility(g, node, expected_type, else_type);
+                    else_type = resolve_type_compatibility(g, context, node, expected_type, else_type);
                 }
 
 
                 if (expected_type) {
                     return_type = (then_type->id == TypeTableEntryIdUnreachable) ? else_type : then_type;
                 } else {
-                    return_type = resolve_peer_type_compatibility(g, node,
+                    return_type = resolve_peer_type_compatibility(g, context, node,
                             node->data.if_expr.then_block, node->data.if_expr.else_node,
                             then_type, else_type);
                 }
@@ -1482,7 +1496,7 @@ static TypeTableEntry * analyze_expression(CodeGen *g, ImportTableEntry *import,
             zig_unreachable();
     }
     assert(return_type);
-    resolve_type_compatibility(g, node, expected_type, return_type);
+    resolve_type_compatibility(g, context, node, expected_type, return_type);
 
     node->codegen_node->expr_node.type_entry = return_type;
     node->codegen_node->expr_node.block_context = context;
diff --git a/src/analyze.hpp b/src/analyze.hpp
index 71fdc3bfb5..4a18026a54 100644
--- a/src/analyze.hpp
+++ b/src/analyze.hpp
@@ -17,6 +17,7 @@ struct FnTableEntry;
 struct BlockContext;
 struct TypeTableEntry;
 struct VariableTableEntry;
+struct CastNode;
 
 struct TypeTableEntryPointer {
     TypeTableEntry *pointer_child;
@@ -213,7 +214,7 @@ struct BlockContext {
     FnTableEntry *fn_entry; // null at the module scope
     BlockContext *parent; // null when this is the root
     HashMap<Buf *, VariableTableEntry *, buf_hash, buf_eql_buf> variable_table;
-    ZigList<AstNode *> cast_expr_alloca_list;
+    ZigList<CastNode *> cast_expr_alloca_list;
     LLVMZigDIScope *di_scope;
 };
 
@@ -261,6 +262,8 @@ struct CastNode {
     // if op is CastOpArrayToString, this will be a pointer to
     // the string struct on the stack
     LLVMValueRef ptr;
+    TypeTableEntry *type;
+    AstNode *source_node;
 };
 
 struct ExprNode {
@@ -270,7 +273,6 @@ struct ExprNode {
     BlockContext *block_context;
 
     // may be null for no cast
-    TypeTableEntry *cast_type;
     CastNode implicit_cast;
 };
 
diff --git a/src/codegen.cpp b/src/codegen.cpp
index f81d07faa6..c51b137f1d 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -1039,7 +1039,7 @@ static LLVMValueRef gen_expr(CodeGen *g, AstNode *node) {
     assert(node->codegen_node);
 
     TypeTableEntry *actual_type = node->codegen_node->expr_node.type_entry;
-    TypeTableEntry *cast_type = node->codegen_node->expr_node.cast_type;
+    TypeTableEntry *cast_type = node->codegen_node->expr_node.implicit_cast.type;
 
     return cast_type ? gen_bare_cast(g, node, val, actual_type, cast_type,
             &node->codegen_node->expr_node.implicit_cast) : val;
@@ -1248,12 +1248,9 @@ static void do_code_gen(CodeGen *g) {
 
             // allocate structs which are the result of casts
             for (int cea_i = 0; cea_i < block_context->cast_expr_alloca_list.length; cea_i += 1) {
-                AstNode *cast_expr_node = block_context->cast_expr_alloca_list.at(cea_i);
-                assert(cast_expr_node->type == NodeTypeCastExpr);
-                CastNode *cast_codegen = &cast_expr_node->codegen_node->data.cast_node;
-                TypeTableEntry *type_entry = get_type_for_type_node(g, cast_expr_node->data.cast_expr.type);
-                add_debug_source_node(g, cast_expr_node);
-                cast_codegen->ptr = LLVMBuildAlloca(g->builder, type_entry->type_ref, "");
+                CastNode *cast_node = block_context->cast_expr_alloca_list.at(cea_i);
+                add_debug_source_node(g, cast_node->source_node);
+                cast_node->ptr = LLVMBuildAlloca(g->builder, cast_node->type->type_ref, "");
             }
         }
 
diff --git a/test/run_tests.cpp b/test/run_tests.cpp
index 2a7746c4d0..66df737845 100644
--- a/test/run_tests.cpp
+++ b/test/run_tests.cpp
@@ -121,7 +121,7 @@ static void add_compiling_test_cases(void) {
         }
 
         fn this_is_a_function() -> unreachable {
-            print_str("OK\n" as string);
+            print_str("OK\n");
             exit(0);
         }
     )SOURCE", "OK\n");
@@ -137,7 +137,7 @@ static void add_compiling_test_cases(void) {
         /// this is a documentation comment
         /// doc comment line 2
         pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
-            print_str(/* mid-line comment /* nested */ */ "OK\n" as string);
+            print_str(/* mid-line comment /* nested */ */ "OK\n");
             return 0;
         }
     )SOURCE", "OK\n");
@@ -185,17 +185,17 @@ static void add_compiling_test_cases(void) {
 
         pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
             if 1 != 0 {
-                print_str("1 is true\n" as string);
+                print_str("1 is true\n");
             } else {
-                print_str("1 is false\n" as string);
+                print_str("1 is false\n");
             }
             if 0 != 0 {
-                print_str("0 is true\n" as string);
+                print_str("0 is true\n");
             } else if 1 - 1 != 0 {
-                print_str("1 - 1 is true\n" as string);
+                print_str("1 - 1 is true\n");
             }
             if !(0 != 0) {
-                print_str("!0 is true\n" as string);
+                print_str("!0 is true\n");
             }
             return 0;
         }
@@ -210,7 +210,7 @@ static void add_compiling_test_cases(void) {
 
         pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
             if add(22, 11) == 33 {
-                print_str("pass\n" as string);
+                print_str("pass\n");
             }
             return 0;
         }
@@ -223,7 +223,7 @@ static void add_compiling_test_cases(void) {
             if a == 0 {
                 goto done;
             }
-            print_str("loop\n" as string);
+            print_str("loop\n");
             loop(a - 1);
 
         done:
@@ -243,7 +243,7 @@ pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
     const a : i32 = 1;
     const b = 2 as i32;
     if (a + b == 3) {
-        print_str("OK\n" as string);
+        print_str("OK\n");
     }
     return 0;
 }
@@ -253,10 +253,10 @@ pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
 use "std.zig";
 
 pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
-    if (true)   { print_str("OK 1\n" as string); }
-    if (false)  { print_str("BAD 1\n" as string); }
-    if (!true)  { print_str("BAD 2\n" as string); }
-    if (!false) { print_str("OK 2\n" as string); }
+    if (true)   { print_str("OK 1\n"); }
+    if (false)  { print_str("BAD 1\n"); }
+    if (!true)  { print_str("BAD 2\n"); }
+    if (!false) { print_str("OK 2\n"); }
     return 0;
 }
     )SOURCE", "OK 1\nOK 2\n");
@@ -267,14 +267,14 @@ use "std.zig";
 pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
     if (true) {
         const no_conflict : i32 = 5;
-        if (no_conflict == 5) { print_str("OK 1\n" as string); }
+        if (no_conflict == 5) { print_str("OK 1\n"); }
     }
 
     const c = {
         const no_conflict = 10 as i32;
         no_conflict
     };
-    if (c == 10) { print_str("OK 2\n" as string); }
+    if (c == 10) { print_str("OK 2\n"); }
     return 0;
 }
     )SOURCE", "OK 1\nOK 2\n");
@@ -290,7 +290,7 @@ pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
 fn void_fun(a : i32, b : void, c : i32) {
     const v = b;
     const vv : void = if (a == 1) {v} else {};
-    if (a + c == 3) { print_str("OK\n" as string); }
+    if (a + c == 3) { print_str("OK\n"); }
     return vv;
 }
     )SOURCE", "OK\n");
@@ -300,14 +300,14 @@ use "std.zig";
 
 pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
     var zero : i32;
-    if (zero == 0) { print_str("zero\n" as string); }
+    if (zero == 0) { print_str("zero\n"); }
 
     var i = 0 as i32;
 loop_start:
     if i == 3 {
         goto done;
     }
-    print_str("loop\n" as string);
+    print_str("loop\n");
     i = i + 1;
     goto loop_start;
 done:
@@ -346,7 +346,7 @@ loop_2_start:
 loop_2_end:
 
     if accumulator == 15 {
-        print_str("OK\n" as string);
+        print_str("OK\n");
     }
 
     return 0;
@@ -358,7 +358,7 @@ loop_2_end:
 use "std.zig";
 
 export fn main(argc : isize, argv : &&u8, env : &&u8) -> i32 {
-    print_str("Hello, world!\n" as string);
+    print_str("Hello, world!\n");
     return 0;
 }
     )SOURCE", "Hello, world!\n");
@@ -368,20 +368,20 @@ export fn main(argc : isize, argv : &&u8, env : &&u8) -> i32 {
 use "std.zig";
 
 export fn main(argc : isize, argv : &&u8, env : &&u8) -> i32 {
-    if false || false || false { print_str("BAD 1\n" as string); }
-    if true && true && false   { print_str("BAD 2\n" as string); }
-    if 1 | 2 | 4 != 7          { print_str("BAD 3\n" as string); }
-    if 3 ^ 6 ^ 8 != 13         { print_str("BAD 4\n" as string); }
-    if 7 & 14 & 28 != 4        { print_str("BAD 5\n" as string); }
-    if 9  << 1 << 2 != 9  << 3 { print_str("BAD 6\n" as string); }
-    if 90 >> 1 >> 2 != 90 >> 3 { print_str("BAD 7\n" as string); }
-    if 100 - 1 + 1000 != 1099  { print_str("BAD 8\n" as string); }
-    if 5 * 4 / 2 % 3 != 1      { print_str("BAD 9\n" as string); }
-    if 5 as i32 as i32 != 5    { print_str("BAD 10\n" as string); }
-    if !!false                 { print_str("BAD 11\n" as string); }
-    if 7 != --7                { print_str("BAD 12\n" as string); }
+    if false || false || false { print_str("BAD 1\n"); }
+    if true && true && false   { print_str("BAD 2\n"); }
+    if 1 | 2 | 4 != 7          { print_str("BAD 3\n"); }
+    if 3 ^ 6 ^ 8 != 13         { print_str("BAD 4\n"); }
+    if 7 & 14 & 28 != 4        { print_str("BAD 5\n"); }
+    if 9  << 1 << 2 != 9  << 3 { print_str("BAD 6\n"); }
+    if 90 >> 1 >> 2 != 90 >> 3 { print_str("BAD 7\n"); }
+    if 100 - 1 + 1000 != 1099  { print_str("BAD 8\n"); }
+    if 5 * 4 / 2 % 3 != 1      { print_str("BAD 9\n"); }
+    if 5 as i32 as i32 != 5    { print_str("BAD 10\n"); }
+    if !!false                 { print_str("BAD 11\n"); }
+    if 7 != --7                { print_str("BAD 12\n"); }
 
-    print_str("OK\n" as string);
+    print_str("OK\n");
     return 0;
 }
     )SOURCE", "OK\n");
@@ -390,19 +390,19 @@ export fn main(argc : isize, argv : &&u8, env : &&u8) -> i32 {
 use "std.zig";
 
 export fn main(argc : isize, argv : &&u8, env : &&u8) -> i32 {
-    if true || { print_str("BAD 1\n" as string); false } {
-      print_str("OK 1\n" as string);
+    if true || { print_str("BAD 1\n"); false } {
+      print_str("OK 1\n");
     }
-    if false || { print_str("OK 2\n" as string); false } {
-      print_str("BAD 2\n" as string);
+    if false || { print_str("OK 2\n"); false } {
+      print_str("BAD 2\n");
     }
 
-    if true && { print_str("OK 3\n" as string); false } {
-      print_str("BAD 3\n" as string);
+    if true && { print_str("OK 3\n"); false } {
+      print_str("BAD 3\n");
     }
-    if false && { print_str("BAD 4\n" as string); false } {
+    if false && { print_str("BAD 4\n"); false } {
     } else {
-      print_str("OK 4\n" as string);
+      print_str("OK 4\n");
     }
 
     return 0;
@@ -414,20 +414,20 @@ use "std.zig";
 
 export fn main(argc : isize, argv : &&u8, env : &&u8) -> i32 {
     var i : i32 = 0;
-    i += 5;  if i != 5  { print_str("BAD +=\n" as string); }
-    i -= 2;  if i != 3  { print_str("BAD -=\n" as string); }
-    i *= 20; if i != 60 { print_str("BAD *=\n" as string); }
-    i /= 3;  if i != 20 { print_str("BAD /=\n" as string); }
-    i %= 11; if i != 9  { print_str("BAD %=\n" as string); }
-    i <<= 1; if i != 18 { print_str("BAD <<=\n" as string); }
-    i >>= 2; if i != 4  { print_str("BAD >>=\n" as string); }
+    i += 5;  if i != 5  { print_str("BAD +=\n"); }
+    i -= 2;  if i != 3  { print_str("BAD -=\n"); }
+    i *= 20; if i != 60 { print_str("BAD *=\n"); }
+    i /= 3;  if i != 20 { print_str("BAD /=\n"); }
+    i %= 11; if i != 9  { print_str("BAD %=\n"); }
+    i <<= 1; if i != 18 { print_str("BAD <<=\n"); }
+    i >>= 2; if i != 4  { print_str("BAD >>=\n"); }
     i = 6;
-    i &= 5;  if i != 4  { print_str("BAD &=\n" as string); }
-    i ^= 6;  if i != 2  { print_str("BAD ^=\n" as string); }
+    i &= 5;  if i != 4  { print_str("BAD &=\n"); }
+    i ^= 6;  if i != 2  { print_str("BAD ^=\n"); }
     i = 6;
-    i |= 3;  if i != 7  { print_str("BAD |=\n" as string); }
+    i |= 3;  if i != 7  { print_str("BAD |=\n"); }
 
-    print_str("OK\n" as string);
+    print_str("OK\n");
     return 0;
 }
     )SOURCE", "OK\n");
@@ -578,7 +578,7 @@ struct Foo {
 }
 fn test_foo(foo : Foo) {
     if foo.b {
-        print_str("OK\n" as string);
+        print_str("OK\n");
     }
 }
     )SOURCE", "OK\n");
@@ -590,10 +590,10 @@ const g1 : i32 = 1233 + 1;
 var g2 : i32;
 
 export fn main(argc : isize, argv : &&u8, env : &&u8) -> i32 {
-    if g2 != 0 { print_str("BAD\n" as string); }
+    if g2 != 0 { print_str("BAD\n"); }
     g2 = g1;
-    if g2 != 1234 { print_str("BAD\n" as string); }
-    print_str("OK\n" as string);
+    if g2 != 1234 { print_str("BAD\n"); }
+    print_str("OK\n");
     return 0;
 }
     )SOURCE", "OK\n");