Trac issueshttps://gitlab.torproject.org/legacy/trac/-/issues2020-06-13T15:28:00Zhttps://gitlab.torproject.org/legacy/trac/-/issues/26785older gccs don't accept -Wunused-const-variable2020-06-13T15:28:00ZTaylor Yuolder gccs don't accept -Wunused-const-variableIn src/common/compress_zstd.c, we use the `DISABLE_GCC_WARNING()` macro to disable the `-Wunused-const-variable` warning. Some versions of gcc don't recognize that warning option, so they will warn about incorrect pragma usage.
```
src...In src/common/compress_zstd.c, we use the `DISABLE_GCC_WARNING()` macro to disable the `-Wunused-const-variable` warning. Some versions of gcc don't recognize that warning option, so they will warn about incorrect pragma usage.
```
src/common/compress_zstd.c:29:1: warning: unknown option after ‘#pragma GCC diagnostic’ kind [-Wpragmas]
DISABLE_GCC_WARNING(unused-const-variable)
^
```
We should probably define a macro if `-Wunused-const-variable` is supported by gcc and update the preprocessor conditional in compress_zstd.c
```
#ifdef HAVE_ZSTD
DISABLE_GCC_WARNING(unused-const-variable)
```
to use it.
Reported on IRC.
Confirmed on Xenial with gcc 5.4.0-6ubuntu1~16.04.10 and libzstd1-dev 1.3.1+dfsg-1~ubuntu0.16.04.1. Travis is still on Trusty so doesn't have a libzstd-dev.
This might be a regression on platforms with libzstd but an older gcc.Tor: 0.3.2.x-finalTaylor YuTaylor Yu