如何修复警告：初始化程序周围缺少大括号？答案

【问题标题】：How to repair warning: missing braces around initializer?如何修复警告：初始化程序周围缺少大括号？
【发布时间】：2012-11-24 14:59:36
【问题描述】：

警告是由vala生成的c代码产生的。

警告：初始化器周围缺少大括号

代码有效，但警告很烦人。警告引用的vala代码是

struct Position {uint x; uint y;}
private static Position positions[8];

生成的C代码是

static Position det_positions[8] = {0};

我尝试了六种不同的方式初始化位置，但似乎无法获得满足警告的语法。这是GCC bug 53119 还是有办法解决它？

【问题讨论】：

我没有在 GCC 4.6.3 上使用 Vala 0.16 或 0.18 收到此警告。愿意分享您的环境吗？另外，导致问题的生成 C 是什么？
@apmasell 嵌入式 linux 目标是 Leopardboard 368，GCC 是 4.4.1，工具链是 codesourcery/arm-2010q1，我已将生成的 C 添加到问题中。我还正确格式化了我之前忘记做的代码。

标签： gcc vala

【解决方案1】：

是的，这似乎与GCC bug 53119 有关。如果您将 C 声明更改为 {{0}}，它就会消失。您的选择是：

忽略警告。
使用 sed 等在生成后操作 C 代码以在该行上使用 {{0}} 而不是 {0}。
在 Vala 中声明数组extern，并在别处编写 C 定义。（#2 的永久版本。）
执行struct foo { int bar; Position positions[8]; } static foo position_holder 和{0} 之类的操作将初始化position_holder.bar，这很好，警告就会消失。

【讨论】：

或在编译中添加“-Wno-missing-braces”以消除无效警告。
但是请注意，警告通常不是无效的！仅对于零初始化（即= {0}），它总是无效的。有关警告的有效案例，请参阅 Adit Ya's answer。

【解决方案2】：

当设置了 -Wall 编译器标志的多维数组被视为线性数组（尽管它仍然正确并且代码运行完美）时也会出现此警告。

例如

char array[5][10][2] = {\
"0","0","0","0","0","0","0","0","0","0",\
"1","1","1","1","1","1","1","1","1","1",\
"2","2","2","2","2","2","2","2","2","2",\
"3","3","3","3","3","3","3","3","3","3",\
"4","4","4","4","4","4","4","4","4","4" };

这将产生警告。

进行以下更改以删除如下所示的警告

char array[5][10][2] = {\
{"0","0","0","0","0","0","0","0","0","0" },\
{"1","1","1","1","1","1","1","1","1","1"},\
{"2","2","2","2","2","2","2","2","2","2"},\
{"3","3","3","3","3","3","3","3","3","3"},\
{"4","4","4","4","4","4","4","4","4","4"} };

如果我错了，请纠正我。

【讨论】：

在本例中，数组的第一级和第二级用{ 输入，第三级通过定义字符串（以'\0' 结尾）用" 输入。在 2D 中，如果您还使用字符串，则仅使用一级{：{"0"} 即char '0' 然后char '\0' 后跟零，如果您不使用字符串，则使用两级{： {{0}} 即只有零。