From 7c61d651fd0e42b8f68840a3735ed7e46d4fd083 Mon Sep 17 00:00:00 2001 From: Cary Coutant Date: Wed, 26 Aug 2015 00:03:04 -0700 Subject: [PATCH] Fix problem where script specified both address and region for a section. If a script specifies both address and region for an output section declaration, gold ignores the region specification. This can lead to bogus "moves backward" errors. This patch fixes gold so that if a section specifies both address and region, it will place the section at the specified address in the region, and update the location counter within the region. gold/ PR gold/18847 * script-sections.cc (Memory_region::set_address): New method. (Script_sections::find_memory_region): Add explicit_only parameter. (Output_section_definition::set_section_addresses): Handle case where script specifies both address and vma region. * script-sections.h (Script_sections::find_memory_region): Add explicit_only parameter. --- gold/ChangeLog | 10 ++++++++ gold/script-sections.cc | 61 ++++++++++++++++++++++++++++++++++--------------- gold/script-sections.h | 2 +- 3 files changed, 54 insertions(+), 19 deletions(-) diff --git a/gold/ChangeLog b/gold/ChangeLog index fdc70155..5d0a764 100644 --- a/gold/ChangeLog +++ b/gold/ChangeLog @@ -1,5 +1,15 @@ 2015-08-25 Cary Coutant + PR gold/18847 + * script-sections.cc (Memory_region::set_address): New method. + (Script_sections::find_memory_region): Add explicit_only parameter. + (Output_section_definition::set_section_addresses): Handle case where + script specifies both address and vma region. + * script-sections.h (Script_sections::find_memory_region): Add + explicit_only parameter. + +2015-08-25 Cary Coutant + PR gold/18859 * object.cc (Input_objects::add_object): Store objects in a map, indexed by soname; update as-needed flag when necessary. diff --git a/gold/script-sections.cc b/gold/script-sections.cc index 3e377aa..261e8e3 100644 --- a/gold/script-sections.cc +++ b/gold/script-sections.cc @@ -93,7 +93,23 @@ class Memory_region script_exp_binary_add(this->start_, script_exp_integer(this->current_offset_)); } - + + void + set_address(uint64_t addr, const Symbol_table* symtab, const Layout* layout) + { + uint64_t start = this->start_->eval(symtab, layout, false); + uint64_t len = this->length_->eval(symtab, layout, false); + if (addr < start || addr >= start + len) + gold_error(_("address 0x%llx is not within region %s"), + static_cast(addr), + this->name_.c_str()); + else if (addr < start + this->current_offset_) + gold_error(_("address 0x%llx moves dot backwards in region %s"), + static_cast(addr), + this->name_.c_str()); + this->current_offset_ = addr - start; + } + void increment_offset(std::string section_name, uint64_t amount, const Symbol_table* symtab, const Layout* layout) @@ -105,7 +121,7 @@ class Memory_region gold_error(_("section %s overflows end of region %s"), section_name.c_str(), this->name_.c_str()); } - + // Returns true iff there is room left in this region // for AMOUNT more bytes of data. bool @@ -120,7 +136,7 @@ class Memory_region // are compatible with this region's attributes. bool attributes_compatible(elfcpp::Elf_Xword flags, elfcpp::Elf_Xword type) const; - + void add_section(Output_section_definition* sec, bool vma) { @@ -2237,6 +2253,7 @@ Memory_region* Script_sections::find_memory_region( Output_section_definition* section, bool find_vma_region, + bool explicit_only, Output_section_definition** previous_section_return) { if (previous_section_return != NULL) @@ -2282,15 +2299,18 @@ Script_sections::find_memory_region( } } - // Make a note of the first memory region whose attributes - // are compatible with the section. If we do not find an - // explicit region assignment, then we will return this region. - Output_section* out_sec = section->get_output_section(); - if (first_match == NULL - && out_sec != NULL - && (*mr)->attributes_compatible(out_sec->flags(), - out_sec->type())) - first_match = *mr; + if (!explicit_only) + { + // Make a note of the first memory region whose attributes + // are compatible with the section. If we do not find an + // explicit region assignment, then we will return this region. + Output_section* out_sec = section->get_output_section(); + if (first_match == NULL + && out_sec != NULL + && (*mr)->attributes_compatible(out_sec->flags(), + out_sec->type())) + first_match = *mr; + } } // With LMA computations, if an explicit region has not been specified then @@ -2350,8 +2370,7 @@ Output_section_definition::set_section_addresses(Symbol_table* symtab, ; else if (this->address_ == NULL) { - vma_region = script_sections->find_memory_region(this, true, NULL); - + vma_region = script_sections->find_memory_region(this, true, false, NULL); if (vma_region != NULL) address = vma_region->get_current_address()->eval(symtab, layout, false); @@ -2359,9 +2378,15 @@ Output_section_definition::set_section_addresses(Symbol_table* symtab, address = *dot_value; } else - address = this->address_->eval_with_dot(symtab, layout, true, - *dot_value, NULL, NULL, - dot_alignment, false); + { + vma_region = script_sections->find_memory_region(this, true, true, NULL); + address = this->address_->eval_with_dot(symtab, layout, true, + *dot_value, NULL, NULL, + dot_alignment, false); + if (vma_region != NULL) + vma_region->set_address(address, symtab, layout); + } + uint64_t align; if (this->align_ == NULL) { @@ -2405,7 +2430,7 @@ Output_section_definition::set_section_addresses(Symbol_table* symtab, Output_section_definition* previous_section; // Determine if an LMA region has been set for this section. - lma_region = script_sections->find_memory_region(this, false, + lma_region = script_sections->find_memory_region(this, false, false, &previous_section); if (lma_region != NULL) diff --git a/gold/script-sections.h b/gold/script-sections.h index e247ea5..7b2655a 100644 --- a/gold/script-sections.h +++ b/gold/script-sections.h @@ -240,7 +240,7 @@ class Script_sections // Find a memory region that should be used by a given output section. Memory_region* - find_memory_region(Output_section_definition*, bool, + find_memory_region(Output_section_definition*, bool, bool, Output_section_definition**); // Returns true if the provide block of memory is contained -- 2.7.4