https://gcc.gnu.org/g:32f99225bcaae9b792aec143239d17f2b7e2c54b
commit r15-927-g32f99225bcaae9b792aec143239d17f2b7e2c54b
Author: Rainer Orth <r...@cebitec.uni-bielefeld.de>
Date: Thu May 30 15:00:59 2024 +0200
ggc: Reduce GGC_QUIRE_SIZE on Solaris/SPARC [PR115031]
g++.dg/modules/pr99023_b.X currently FAILs on 32-bit Solaris/SPARC:
FAIL: g++.dg/modules/pr99023_b.X -std=c++2a 1 blank line(s) in output
FAIL: g++.dg/modules/pr99023_b.X -std=c++2a (test for excess errors)
Excess errors:
cc1plus: out of memory allocating 1048344 bytes after a total of 7913472
bytes
It turns out that this exhaustion of the 32-bit address space happens
due to a combination of three issues:
* the SPARC pagesize of 8 kB,
* ggc-page.cc's chunk size of 512 * pagesize, i.e. 4 MB, and
* mmap adding two 8 kB unmapped red-zone pages to each mapping
which result in the 4 MB mappings to actually consume 4.5 MB of address
space.
To avoid this, this patch reduces the chunk size so it remains at 4 MB
even when combined with the red-zone pages, as recommended by mmap(2).
Tested on sparc-sun-solaris2.11 and sparcv9-sun-solaris2.11.
2024-05-29 Rainer Orth <r...@cebitec.uni-bielefeld.de>
gcc:
PR c++/115031
* config/sparc/sol2.h (GGC_QUIRE_SIZE): Define as 510.
Diff:
---
gcc/config/sparc/sol2.h | 3 +++
1 file changed, 3 insertions(+)
diff --git a/gcc/config/sparc/sol2.h b/gcc/config/sparc/sol2.h
index 552f58b2cc8..530e681aaee 100644
--- a/gcc/config/sparc/sol2.h
+++ b/gcc/config/sparc/sol2.h
@@ -38,6 +38,9 @@ along with GCC; see the file COPYING3. If not see
#undef SPARC_DEFAULT_CMODEL
#define SPARC_DEFAULT_CMODEL CM_MEDMID
+/* Redue ggc-page.cc's chunk size to account for mmap red-zone pages. */
+#define GGC_QUIRE_SIZE 510
+
/* Select a format to encode pointers in exception handling data. CODE
is 0 for data, 1 for code labels, 2 for function pointers. GLOBAL is
true if the symbol may be affected by dynamic relocations.
