[PATCH] support ggc hash_map and hash_set

[Alan Lawrence]

Following this, we're seeing ICEs in tests in gcc.dg/pch.exp and g++.dg/pch.exp,
with cross-builds (hosted on x86_64) targetting bare metal AArch64 and ARM
(aarch64-none-elf, aarch64_be-none-elf and arm-none-eabi; I haven't tested
armeb-none-eabi; builds targeting linux are OK), for *release builds only*.

Affected tests:

gcc.dg/pch.exp: all variants of
./except-1.h
./inline-3.h
gcc.dg/pch/except-1.c
gcc.dg/pch/inline-3.c

g++.dg: all variants of
./array-1.H
./empty.H
./externc-1.H
./local-1.H
./pch.H
./static-1.H
./system-1.H
./system-2.H
./template-1.H
./uninst.H
./wchar-1.H

(These then lead to failures of g++.dg/pch/{array-1,...}.C and corresponding
assembly comparisons).

Sample log:

Executing on host: build/obj/gcc2/gcc/testsuite/g++/../../xg++
-Bbuild/obj/gcc2/gcc/testsuite/g++/../../ ./template-1.H
-fno-diagnostics-show-caret -fdiagnostics-color=never  -nostdinc++
-Ibuild/obj/gcc2/aarch64-none-elf/ilp32/libstdc++-v3/include/aarch64-none-elf
-Ibuild/obj/gcc2/aarch64-none-elf/ilp32/libstdc++-v3/include
-Isrc/gcc/libstdc++-v3/libsupc++ -Isrc/gcc/libstdc++-v3/include/backward
-Isrc/gcc/libstdc++-v3/testsuite/util -fmessage-length=0  -O2 -g
-specs=aem-ve.specs    -mabi=ilp32 -mcmodel=small  -o template-1.H.gch
(timeout = 300)
spawn build/obj/gcc2/gcc/testsuite/g++/../../xg++
-Bbuild/obj/gcc2/gcc/testsuite/g++/../../ ./template-1.H
-fno-diagnostics-show-caret -fdiagnostics-color=never -nostdinc++
-Ibuild/obj/gcc2/aarch64-none-elf/ilp32/libstdc++-v3/include/aarch64-none-elf
-Ibuild/obj/gcc2/aarch64-none-elf/ilp32/libstdc++-v3/include
-Isrc/gcc/libstdc++-v3/libsupc++ -Isrc/gcc/libstdc++-v3/include/backward
-Isrc/gcc/libstdc++-v3/testsuite/util -fmessage-length=0 -O2 -g
-specs=aem-ve.specs -mabi=ilp32 -mcmodel=small -o template-1.H.gch

./template-1.H:5:2: internal compiler error: in relocate_ptrs, at ggc-common.c:435
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
compiler exited with status 1
output is:
./array-1.H:4:2: internal compiler error: in relocate_ptrs, at ggc-common.c:435
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

FAIL: ./array-1.H  -g (internal compiler error)
FAIL: ./array-1.H  -g (test for excess errors)
Excess errors:
./array-1.H:4:2: internal compiler error: in relocate_ptrs, at ggc-common.c:435

--Alan

tsaunders@mozilla.com wrote:
> From: Trevor Saunders <tsaunders@mozilla.com>
>
> Hi,
>
> There are still some issues to make this work really nicely, but this part is
> probably good enough its worth reviewing.
>
> For one thing you can't use ggc hash_map or set in front ends with some types
> or gengtype will decide to put the overloads of the marking routines it
> provides in a front end file instead of the one it choose before breaking other
> front ends.  However that seems to be an unrelated issue you can trigger it
> without using hash_map/set, so we might as well solve it separetly.
>
> I had to have the entry marking functions for set deligate to the traits class
> because gcc < 4.9.1 issues clearly bogus errors if you inline the code from the
> traits implementation.  We may well want to make map work the same way at some
> point to enable some of the special GTY attributes like if_marked, but it
> doesn't seem to be necessary right now.
>
> bootstrapped + regtested without regressions on x86_64-unknown-linux-gnu, ok?
>
> Trev
>