Prior to this patch, the semantics utility GetExpr() will crash
unconditionally if it encounters a typed expression in the parse
tree that has not been set by expression semantics. This is the
right behavior when called from lowering, by which time it is known
that the program had no fatal user errors, since it signifies a
fatal internal error. However, prior to lowering, in the statement
semantics checking code, a more nuanced test should be used before
crashing -- specifically, we should not crash in the face of a
missing typed expression when in error recovery mode.
Getting this right requires GetExpr() and its helper class to have
access to the semantics context, so that it can check AnyFatalErrors()
before crashing. So this patch touches nearly all of its call sites.
Differential Revision: https://reviews.llvm.org/D123873
Derived types with allocatable and pointer components cannot
be used in I/O data transfer statements unless they have defined
I/O procedures available (as type-bound or regular generics).
These cases are caught as errors by the I/O runtime library,
but it would be better if they were flagged during compilation.
(Address comment in review: don't use explicit name string lengths.)
Differential Revision: https://reviews.llvm.org/D120675
Fold the legacy intrinsic functions LGE, LGT, LLE, & LLT
by rewriting them into character relational expressions and
then folding those. Also fix folding of comparisons of
character values of distinct lengths: the shorter value must
be padded with blanks. (This fix exposed some bad test cases,
which are also fixed.)
Differential Revision: https://reviews.llvm.org/D111843
A number of I/O syntax rules involve variables that will be written to,
and must therefore be definable. This includes internal file variables,
IOSTAT= and IOMSG= specifiers, most INQUIRE statement specifiers, a few
other specifiers, and input variables. This patch checks for
these violations, and implements several additional I/O TODO constraint
checks.
Differential Revision: https://reviews.llvm.org/D86557