Close https://github.com/llvm/llvm-project/issues/71034
See
https://discourse.llvm.org/t/rfc-c-20-modules-introduce-thin-bmi-and-decls-hash/74755
This patch introduces reduced BMI, which doesn't contain the definitions
of functions and variables if its definitions won't contribute to the
ABI.
Testing is a big part of the patch. We want to make sure the reduced BMI
contains the same behavior with the existing and relatively stable
fatBMI. This is pretty helpful for further reduction.
The user interfaces part it left to following patches to ease the
reviewing.
Close https://github.com/llvm/llvm-project/issues/60275
The root cause of issue 60275 is the imbalance of
PushExpressionEvaluationContext() and PopExpressionEvaluationContext().
See
f1c4f927f7/clang/lib/Parse/Parser.cpp (L1396-L1437)
We will PushExpressionEvaluationContext() in ActOnStartOfFunctionDef()
in line 1396 and we should pop it in ActOnFinishFunctionBody later.
However if we skip the function body in line 1402, the expression
evaluation context will not be popped. Then here is the issue report. I
fix the issue by inserting codes to pop the expression evaluation
context explicitly if the function body is skipped. Maybe this looks
like an ad-hoc fix. But if we want to fix this in a pretty way, we
should refactor the current framework for pushing and popping expression
evaluation contexts. Currently there are 23
PushExpressionEvaluationContext() callsities and 21
PopExpressionEvaluationContext() callsites in the code. And it seems not
easy to balance them well and fast. So I suggest to land this fix first.
At least it can prevent the crash.
Reviewed By: cor3ntin
Differential Revision: https://reviews.llvm.org/D143053
