From: Daniel Arndt <arndtd@ornl.gov>
Date: Fri, 22 Nov 2019 21:45:56 +0000 (-0500)
Subject: Comment MSVC 2019 DEAL_II_HAVE_CXX14_CONSTEXPR_CAN_CALL_NONCONSTEXPR failure
X-Git-Tag: v9.2.0-rc1~858^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=08a6da17318dfd53457df4a304c1f8a923773939;p=dealii.git

Comment MSVC 2019 DEAL_II_HAVE_CXX14_CONSTEXPR_CAN_CALL_NONCONSTEXPR failure
---

diff --git a/cmake/checks/check_01_cxx_features.cmake b/cmake/checks/check_01_cxx_features.cmake
index 54d0bfa5b2..a80d781c10 100644
--- a/cmake/checks/check_01_cxx_features.cmake
+++ b/cmake/checks/check_01_cxx_features.cmake
@@ -731,6 +731,10 @@ CHECK_CXX_SOURCE_COMPILES(
 # expression, C++14 allows to call non-constexpr functions from constexpr
 # functions. Unfortunately, not all compilers obey the standard in this regard.
 #
+# In some cases, MSVC 2019 crashes with an internal compiler error when we
+# declare the respective functions as 'constexpr' even though the test below
+# passes, see #9080.
+#
 IF(NOT CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
   CHECK_CXX_SOURCE_COMPILES(
     "