[Bug target/114578] New: [13/14 Regression] memory hog, virtual memory exhausted, building a c++ file on arm-linux-gnueabihf

[Bug target/114578] New: [13/14 Regression] memory hog, virtual memory exhausted, building a c++ file on arm-linux-gnueabihf

[doko at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114578

            Bug ID: 114578
           Summary: [13/14 Regression] memory hog, virtual memory
                    exhausted, building a c++ file on arm-linux-gnueabihf
           Product: gcc
           Version: 13.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: doko at gcc dot gnu.org
  Target Milestone: ---

seen with the 13 branch and trunk, building on arm-linux-gnueabihf.

$ g++ -g -O0 -fstack-protector-strong -fno-stack-clash-protection
-fno-exceptions -std=gnu++17 -fvisibility=hidden -fvisibility-inlines-hidden
-fPIC -c qrc_assets.ii
virtual memory exhausted: Cannot allocate memory

the gcc-12 branch is able to build that with -g -O2.

preprocessed source (120MB uncompressed) at
https://people.debian.org/~doko/tmp/qrc_assets.ii.xz

[Bug target/114578] [13/14 Regression] memory hog, virtual memory exhausted, building a c++ file on arm-linux-gnueabihf

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114578

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Time variable                                   usr           sys          wall
          GGC
 phase setup                        :   0.00 (  0%)   0.03 (  0%)   0.10 (  0%)
 1903k (  0%)
 phase parsing                      : 114.74 ( 95%)  45.79 (100%) 160.53 ( 95%)
 6159M (100%)
 phase lang. deferred               :   0.07 (  0%)   0.00 (  0%)   0.07 (  0%)
 9312  (  0%)
 phase opt and generate             :   6.36 (  5%)   0.10 (  0%)   6.46 (  4%)
  293k (  0%)
 phase finalize                     :   0.00 (  0%)   0.06 (  0%)   1.72 (  1%)
    0  (  0%)
 |name lookup                       :   0.00 (  0%)   0.01 (  0%)   0.00 (  0%)
  109k (  0%)
 garbage collection                 :   1.89 (  2%)   0.00 (  0%)   1.89 (  1%)
    0  (  0%)
 callgraph construction             :   6.35 (  5%)   0.09 (  0%)   6.44 (  4%)
   13k (  0%)
 preprocessing                      :  30.74 ( 25%)  24.93 ( 54%)  55.53 ( 33%)
 2047M ( 33%)
 parser (global)                    :  81.10 ( 67%)  20.86 ( 45%) 102.10 ( 60%)
 4111M ( 67%)
 constant expression evaluation     :   1.08 (  1%)   0.00 (  0%)   1.08 (  1%)
  304  (  0%)
 post expand cleanups               :   0.00 (  0%)   0.00 (  0%)   0.01 (  0%)
 2728  (  0%)
 initialize rtl                     :   0.00 (  0%)   0.00 (  0%)   0.01 (  0%)
 9032  (  0%)
 rest of compilation                :   0.01 (  0%)   0.01 (  0%)   0.00 (  0%)
   16k (  0%)
 TOTAL                              : 121.17         45.98        168.88       
 6161M
Extra diagnostic checks enabled; compiler may run slowly.


For x86_64-linux-gnu (but with checking enabled). Definitely a front-end issue.
Preprocessing takes 2G is even more shocking.

[Bug c++/114578] [13/14 Regression] memory hog, virtual memory exhausted, building a c++ file on arm-linux-gnueabihf

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114578

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
               Host|                            |arm-linux-gnueabihf
             Target|arm-linux-gnueabihf         |
          Component|target                      |c++

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Though 111MB preprocessed source makes this a huge one in general but if we say
on average a token is 3 characters and a token takes ~16 bytes each. that does
expand to over 500 MB of memory since we do up front lexing for C++.

[Bug c++/114578] [13/14 Regression] memory hog, virtual memory exhausted, building a c++ file on arm-linux-gnueabihf

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114578

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The real way to fix this is to have `#embed` supported for both C++ and C and
move this code over to use that instead.

[Bug c++/114578] [13/14 Regression] memory hog, virtual memory exhausted, building a c++ file on arm-linux-gnueabihf

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114578

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The code has 3 huge arrays which is definitely a canidate for  `#embed` usage.

[Bug c++/114578] [13/14 Regression] memory hog, virtual memory exhausted, building a c++ file on arm-linux-gnueabihf

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114578

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=105863

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Someone should report this issue to the QT folks to see if they could
reimplement this to use `#embed` (though GCC needs to add #embed support still
but that is PR 105863)

[Bug c++/114578] [13/14 Regression] memory hog, virtual memory exhausted, building a c++ file on arm-linux-gnueabihf

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114578

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |13.3

[Bug c++/114578] [13/14/15 Regression] memory hog, virtual memory exhausted, building a c++ file on arm-linux-gnueabihf

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114578

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|13.3                        |13.4

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 13.3 is being released, retargeting bugs to GCC 13.4.