<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/116950>116950</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
Static inline variable and global are initialized in incorrect order with optimization on
</td>
</tr>
<tr>
<th>Labels</th>
<td>
new issue
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
semushin-s
</td>
</tr>
</table>
<pre>
Please take a look at the following example:
```cpp
struct A {
A() {
a = 1;
}
int a;
};
struct B {
B() : _a(_ca) {}
A _a;
static inline A _ca;
};
B b;
int main() {
return b._a.a;
}
```
Currently it returns 0 with `-O2` using clang:
https://gcc.godbolt.org/z/66hGqoaj8
and returns 1 with `-O0`. Compiled by all the other compilers, it results in 1 as well.
It seems initialization of `static inline A _ca` should be done earlier than initialization of `B`.
According to `[basic.start.dynamic]`:
`if V has partially-ordered initialization, W does not have unordered initialization, and for every definition E of W there exists a definition D of V such that D is appearance-ordered before E ... V is sequenced before the initialization of W;`
Let's say `static inline A _ca` is definition of `V`, `B b` is definition of `W`, seems by appearance order `_ca` should have been initialized before `b`, however with optimization `a=1` initialization fails to happen before initializing `B b` apparently. Please correct me if my interpretation of the standard is wrong in this case.
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJx8VU2PozgQ_TXOpdTIGELCgUPSmaxWWmlXWqn72CpMETxjbMY2ncn8-pUhnz3TG0VKsJ-rXr16ZdB7dTBEFVtu2XK3wDF01lWe-tF3yjz5RW2bU_WPJvQEAb8RIGhrvwEGCB1Ba7W2R2UOQD-wHzSxbMP4jvENK_j8lcMwr_jgRhlgA2y1PWN4uWFizUR5W4PzB4FlO0hZdllnq93l1AWnTAC8IiLg-v8-4_Yh4_aSMdvAGzKxfpN4YfCYItKLkFvQ0gcMSoIyWhmCDcSzn-ffQv1hJTLuUZmPVTNeOgqjM1Anb5g8Bn3U8z7c8-gcmaBPoALMATxwOKrQASv409-CFRxGHxskNZrDtT1dCIOPT2LPxP4gZXKwTW11SKw7MLH_ycS-KLo_vlv8up6PoGmuOdK7HJFUAs-2H5SmBuoToNaTO2zoyIGcd5xn4nnm6UcdPCgDKaCHI2md3Ff1ZwBP1EeECgq1-olBWQO2jQl_14KCg-_sqBuoCRprCAidVuQgdGh-H2cbac8JN1Ja10SRgo1bbLmt0SuZ-IAuJM3JYK8kW-7i3p3BVQsv0KGHAV1MoE9P1jXkqPmQMlb-Co0lD8YG6PCdYDSfY6PUrXVA7-RO0FA7QayBL5H8axTXEdAP5YMHvAfsIuAF_Ci7WHuAHSgPOAyEDo2kK8GaWusIvkCSJPASQZ6-j2TkbS-28FfpXqM3H234FwUmVh48nv6nQ8rfE52b8BIjieepH1B_hno9o2ZXRINd64Gpngh69MEkcU101_xbYazg9TlkZ49R5NnOdgiqv5TKCo4s26UTqUcVWlTaR690kYi5hL2iopNuFeEw4DylCZxvUmmdIxmgJ1At9Kd4k5EbHIWrzFF8H9A06JooytFZc4gzEzrlQaKnh5lZNFXWlFmJC6rSVSZ4ueY8X3RVS0TLcpmWeV5mRNhgm-arYlXnZV6s83ShKsFFnqaCp1xwnictR9lQ0S5l2-bZumA5px6VTrR-7-P1sFDej1SlaVEu-UJjTdpPbxAhDB1h2mVCxBeKq-Khp3o8eJZzHf16CxNU0FT9--CWd3QKa03TCBy0rVED3ms7zQsoc5Fw7v-v7bNmMTpdfbjnVOjGOpG2Z2IfeZx_ngZnv5IMTOwn9p6J_bm890r8FwAA___55jzj">