Update CMake to 3.9 #666
Merged
Update CMake to 3.9 #666
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
graebm
approved these changes
Oct 23, 2024
graebm
added a commit
that referenced
this pull request
Nov 28, 2024
**Issue:** A user had been building aws-crt-cpp with `CXXFLAGS=-D_GLIBCXX_USE_CXX11_ABI=0`, and that worked fine until the recent change where we started hiding symbols by default (PR #666) With symbols hidden by default, and `_GLIBCXX_USE_CXX11_ABI=0`, tests would crash in the destructor of `Aws::Crt::String` (which is `std::string` with a custom allocator). **Description of changes:** Don't hide symbols when building for the ancient glibcxx ABI. I don't 100% understand why this fixes the issue, but the situation is esoteric enough that it doesn't seem worth spending more days on this problem. **Background** See: https://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dual_abi.html GCC had to introduce a new ABI for C++11 which removed the copy-on-write optimization for strings, which is forbidden in C++11 and later (new ABI uses a small-string optimization instead). But GCC let users manually set `_GLIBCXX_USE_CXX11_ABI=0` so they could opt back into the old ABI and continue working with libraries compiled for C++03. I don't think GCC intended devs to continue using this 10 years later, but some people are, because the old copy-on-write optimization has less memory usage.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
See: awslabs/aws-c-common#1159
Issue #, if available:
awslabs/aws-c-common#1142
Description of changes:
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.