Internal compiler error for slowdebug build with gcc 7.5.0 on Ubuntu 18.04

[Volker Simonis]

Hi,

When compiling the latest HS sources in slowdebug mode with gcc 7.5.0
(the default compiler on Ubuntu 18.04) I get the following internal
compiler error for the file compileBroker.cpp:

/OpenJDK/Git/jdk/src/hotspot/share/compiler/compileBroker.cpp: In
static member function 'static voi
d CompileBroker::invoke_compiler_on_method(CompileTask*)':
/OpenJDK/Git/jdk/src/hotspot/share/compiler/compileBroker.cpp:2393:1:
internal compiler error: Max. number of generated reload insns per
insn is achieved (90)

 }
 ^
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-7/README.Bugs> for instructions.

I know that gcc 7.5.0 isn't officially supported but was just curious
if somebody has seen this before? Googling around shows that this
issue seems to have been fixed several times in gcc 4.9 and
specifically for ppc/rs6000.

I've installed and tried gcc 8.4.0 but the error remains the same:

GNU C++14 (Ubuntu 8.4.0-1ubuntu1~18.04) version 8.4.0 (x86_64-linux-gnu)
    compiled by GNU C version 8.4.0, GMP version 6.1.2, MPFR version
4.0.1, MPC version 1.1.0, isl version isl-0.19-GMP

GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
GNU assembler version 2.30 (x86_64-linux-gnu) using BFD version (GNU
Binutils for Ubuntu) 2.30
Compiler executable checksum: 67fba09f596cc8a67df33f8529603bfb
during RTL pass: reload
/OpenJDK/Git/jdk/src/hotspot/share/compiler/compileBroker.cpp: In
static member function ‘static void
CompileBroker::invoke_compiler_on_method(CompileTask*)’:
/OpenJDK/Git/jdk/src/hotspot/share/compiler/compileBroker.cpp:2393:1:
internal compiler error: Max. number of generated reload insns per
insn is achieved (90)

 }
 ^
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-8/README.Bugs> for instructions.

According to the "Supported Build Platforms" Wiki [1] it seems that at
least SAP is using gcc 8. Have you run into this issue as well? Any
ideas how to fix it without upgrading to gcc 10?

Thank you and best regards,
Volker

PS: the release build works perfectly fine with gcc 7.5.0

[1] https://wiki.openjdk.java.net/display/Build/Supported+Build+Platforms