From a54d45c593ccadcd9ea99bb6ad66a7f7de91f855 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Tue, 26 Jan 2016 22:35:20 +0000 Subject: [PATCH] compiler: Avoid knock-on errors with impossibly large types. The gofrontend asks the backend compiler for the architecture appropriate size of a given type. For array types, it is possible to construct a type too large to fit on the machine. This patch does two things: 1. When an impossibly large type is encountered, we mark the type as erroneous and later calls to discover the size of that type are short-circuited. 2. When generating the GC symbol data for an impossibly large array of arrays, we avoid generating symbol data as soon as we find an array that is too large to be expressed. Fixes golang/go#12938. Reviewed-on: https://go-review.googlesource.com/16234 From-SVN: r232855 --- gcc/go/gofrontend/MERGE | 2 +- gcc/go/gofrontend/types.cc | 6 ++++-- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE index b4c90ef8892fa..9540d16b4c81c 100644 --- a/gcc/go/gofrontend/MERGE +++ b/gcc/go/gofrontend/MERGE @@ -1,4 +1,4 @@ -c375f3bf470f94220149b486c947bb3eb57cde7d +731941c155214d6158fa800e52ab3225c0b55f73 The first line of this file holds the git revision number of the last merge done from the gofrontend repository. diff --git a/gcc/go/gofrontend/types.cc b/gcc/go/gofrontend/types.cc index 802a17dc0e381..52a1e4da886f7 100644 --- a/gcc/go/gofrontend/types.cc +++ b/gcc/go/gofrontend/types.cc @@ -2550,6 +2550,8 @@ Type::backend_type_size(Gogo* gogo, int64_t *psize) { if (!this->is_backend_type_size_known(gogo)) return false; + if (this->is_error_type()) + return false; Btype* bt = this->get_backend_placeholder(gogo); *psize = gogo->backend()->type_size(bt); if (*psize == -1) @@ -6453,7 +6455,7 @@ Array_type::slice_gc_symbol(Gogo* gogo, Expression_list** vals, (*vals)->push_back(Expression::make_integer_ul(opval, uintptr_type, bloc)); (*vals)->push_back(*offset); - if (element_size != 0) + if (element_size != 0 && ok) (*vals)->push_back(Expression::make_gc_symbol(element_type)); this->advance_gc_offset(offset); } @@ -6488,7 +6490,7 @@ Array_type::array_gc_symbol(Gogo* gogo, Expression_list** vals, Type* element_type = this->element_type(); if (bound < 1 || !element_type->has_pointer()) this->advance_gc_offset(offset); - else if (bound == 1 || iwidth <= 4 * pwidth) + else if (ok && (bound == 1 || iwidth <= 4 * pwidth)) { for (unsigned int i = 0; i < bound; ++i) Type::gc_symbol(gogo, element_type, vals, offset, stack_size);