BUG: Avoid uses -Werror during tests default C/C++ standards

  This may break the test if any unsupported
  compiler options are specified.

  This patch also removes the testing of constexpr and keeps only fold
  expressions and inline variables to avoid triggering the constexpr
  warning warning: ‘if constexpr’ only available with ‘-std=c++17’ or
  ‘-std=gnu++17 by Travis CI, which can cause the build to fail due to warning trapping.

1 files changed, 1 insertions, 4 deletions

diff --git a/setup.py b/setup.py
index d06677ae1..fc16971c9 100755
--- a/setup.py
+++ b/setup.py
@@ -193,9 +193,6 @@ def get_build_overrides():
     from numpy._utils import _pep440
 
     def try_compile(compiler, file, flags = [], verbose=False):
-        # To bypass trapping warnings by Travis CI
-        if getattr(compiler, 'compiler_type', '') == 'unix':
-            flags = ['-Werror'] + flags
         bk_ver = getattr(compiler, 'verbose', False)
         compiler.verbose = verbose
         try:
@@ -270,7 +267,7 @@ def get_build_overrides():
             constexpr bool test_fold = (... && std::is_const_v<T>);
             int main()
             {
-                if constexpr (test_fold<int, const int>) {
+                if (test_fold<int, const int>) {
                     return 0;
                 }
                 else {