Merge ~kzapalowicz/snappy-hwe-snaps/+git/pulseaudio:feature/add-fomit-fpointer-to-pa-cflags into ~snappy-hwe-team/snappy-hwe-snaps/+git/pulseaudio:pulseaudio/8.0

[Konrad Zapałowicz]

Fix build issue on armhf

GCC uses r7 as the frame pointer under ARM. When this register is also
used in the code then there is conflict. The -fomit-frame-pointer cflag
makes sure that the frame pointer is not used.

Fix build issue on armhf

GCC uses r7 as the frame pointer under ARM. When this register is also
used in the code then there is conflict. The -fomit-frame-pointer cflag
makes sure that the frame pointer is not used.

[System Enablement Bot (system-enablement-ci-bot)]

FAILED: Continuous integration, rev:7a93b33f48918e8e679fb9189011366e4972233b
https://jenkins.canonical.com/system-enablement/job/generic-build-snap/525/
Executed test runs:
    FAILURE: https://jenkins.canonical.com/system-enablement/job/generic-run-snap-spread-tests/265/console
    None: https://jenkins.canonical.com/system-enablement/job/generic-update-snap-mp/433/console

Click here to trigger a rebuild:
https://jenkins.canonical.com/system-enablement/job/generic-build-snap/525/rebuild

review: Needs Fixing (continuous-integration)

[Alfonso Sanchez-Beato (alfonsosanchezbeato)]

I am curious about when the logic using r7 was added. Also, is this flag used upstream?

[Konrad Zapałowicz (kzapalowicz)]

It has been there all the time, there are no recent commits to pulseaudio source that we maintain on our side. I suspect that it has been triggered by the change in the infrastructure. Could be one of the following:
 - gcc-armhf version changed
 - snapcraft update which figures out the cflags differently now

However I do not know for sure, have not been running a query ysterday to find out what has changed.

[Alfonso Sanchez-Beato (alfonsosanchezbeato)]

@Konrad, makes sense, I guess the defaults for the compiler have changed. Which is actually nice, that makes getting backtraces possible even without having all the debugging info. But of course in this case we have to disable it...

review: Approve

[Simon Fels (morphis)]

review: Approve

[System Enablement Bot (system-enablement-ci-bot)]

FAILED: Continuous integration, rev:7a93b33f48918e8e679fb9189011366e4972233b
https://jenkins.canonical.com/system-enablement/job/generic-build-snap/566/
Executed test runs:
    FAILURE: https://jenkins.canonical.com/system-enablement/job/generic-run-snap-spread-tests/299/console
    None: https://jenkins.canonical.com/system-enablement/job/generic-update-snap-mp/474/console

Click here to trigger a rebuild:
https://jenkins.canonical.com/system-enablement/job/generic-build-snap/566/rebuild

review: Needs Fixing (continuous-integration)

diff --git a/configure.ac b/configure.ac
index 9250c05..f8e7673 100644
--- a/configure.ac
+++ b/configure.ac
@@ -177,7 +177,7 @@ esac
 #### Compiler flags ####
 
 AX_APPEND_COMPILE_FLAGS(
-    [-Wall -W -Wextra -pipe -Wno-long-long -Wno-overlength-strings -Wunsafe-loop-optimizations -Wundef -Wformat=2 -Wlogical-op -Wsign-compare -Wformat-security -Wmissing-include-dirs -Wformat-nonliteral -Wold-style-definition -Wpointer-arith -Winit-self -Wdeclaration-after-statement -Wfloat-equal -Wmissing-prototypes -Wstrict-prototypes -Wredundant-decls -Wmissing-declarations -Wmissing-noreturn -Wshadow -Wendif-labels -Wcast-align -Wstrict-aliasing -Wwrite-strings -Wno-unused-parameter -ffast-math -fno-common -fdiagnostics-show-option -fdiagnostics-color=auto],
+    [-Wall -W -Wextra -pipe -Wno-long-long -Wno-overlength-strings -Wunsafe-loop-optimizations -Wundef -Wformat=2 -Wlogical-op -Wsign-compare -Wformat-security -Wmissing-include-dirs -Wformat-nonliteral -Wold-style-definition -Wpointer-arith -Winit-self -Wdeclaration-after-statement -Wfloat-equal -Wmissing-prototypes -Wstrict-prototypes -Wredundant-decls -Wmissing-declarations -Wmissing-noreturn -Wshadow -Wendif-labels -Wcast-align -Wstrict-aliasing -Wwrite-strings -Wno-unused-parameter -ffast-math -fno-common -fdiagnostics-show-option -fdiagnostics-color=auto -fomit-frame-pointer],
     [], [-pedantic -Werror])
 
 AS_CASE([" $CFLAGS "], [*" -O0 "*], [], [