[Debian-mobcom-maintainers] Bug#1116696: libgsm FTCBFS: incompatible function prototypes for default gcc-15 languagte standard

[Helmut Grohne]

Source: libgsm
Version: 1.0.22-1
Tags: patch
User: debian-cross at lists.debian.org
Usertags: ftcbfs

libgsm overrides CC for cross building. The upstream's default for CC 
happens to include -ansi though and this is not present in the override. 
Hence, the C standard is higher for cross builds and the code base is 
not compatible with gcc-15's default. I propose adding -ansi to the CC 
variable for cross building as well. More generally, I recommend not 
including any flags in CC and upgrading the code base to a higher C 
standard, but that's beyond the scope of this report. Please find a 
patch attached for the inclusion of the -ansi flag.

Helmut
-------------- next part --------------
diff -Nru libgsm-1.0.22/debian/changelog libgsm-1.0.22/debian/changelog
--- libgsm-1.0.22/debian/changelog	2022-09-30 23:54:15.000000000 +0200
+++ libgsm-1.0.22/debian/changelog	2025-09-29 17:57:36.000000000 +0200
@@ -1,3 +1,10 @@
+libgsm (1.0.22-1.1) UNRELEASED; urgency=medium
+
+  * Non-maintainer upload.
+  * Fix FTCBFS: Include -ansi in overridden CC. (Closes: #-1)
+
+ -- Helmut Grohne <helmut at subdivi.de>  Mon, 29 Sep 2025 17:57:36 +0200
+
 libgsm (1.0.22-1) unstable; urgency=medium
 
   * New upstream release.
diff -Nru libgsm-1.0.22/debian/rules libgsm-1.0.22/debian/rules
--- libgsm-1.0.22/debian/rules	2022-09-30 23:52:26.000000000 +0200
+++ libgsm-1.0.22/debian/rules	2025-09-29 17:57:36.000000000 +0200
@@ -1,7 +1,7 @@
 #! /usr/bin/make -f
 
 ifneq ($(DEB_HOST_GNU_TYPE),$(DEB_BUILD_GNU_TYPE))
-CROSS=CC=$(DEB_HOST_GNU_TYPE)-gcc
+CROSS=CC="$(DEB_HOST_GNU_TYPE)-gcc -ansi"
 else
 CROSS=
 endif