unbreak g++ 4.8 i586 build

OBS-URL: https://build.opensuse.org/package/show/X11:Wayland/spirv-tools?expand=0&rev=9

gcc48.diff

@@ -0,0 +1,30 @@
+From: Jan Engelhardt <jengelh@inai.de>
+Date: 2017-02-02 19:42:44.679588946 +0100
+
+build: workaround gcc 4.8 bug
+
+tools/io.h:41:38:
+error: ignoring return value of 'long int ftell(FILE*)',
+declared with attribute warn_unused_result [-Werror=unused-result,-Werror]
+       if (sizeof(T) != 1 && (ftell(fp) % sizeof(T))) {
+
+Workaround gcc 4.8's wrongful idea that ftell's return value
+were ignored.
+---
+ tools/io.h |    3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+Index: spirv-tools-2016.7~g24/tools/io.h
+===================================================================
+--- spirv-tools-2016.7~g24.orig/tools/io.h
++++ spirv-tools-2016.7~g24/tools/io.h
+@@ -38,7 +38,8 @@ bool ReadFile(const char* filename, cons
+         return false;
+       }
+     } else {
+-      if (sizeof(T) != 1 && (ftell(fp) % sizeof(T))) {
++      long ftx = ftell(fp);
++      if (sizeof(T) != 1 && ftx % sizeof(T) != 0) {
+         fprintf(stderr, "error: corrupted word found in file '%s'\n", filename);
+         return false;
+       }

spirv-tools.changes

@@ -11,6 +11,7 @@ Thu Feb  2 10:35:57 UTC 2017 - jengelh@inai.de
   * Allow missing memory model instructions in modules.
   * Add spirv-lesspipe.sh
   * Add spirv-dis/spirv-as support for emacs when loading .spv binaries
+- Add gcc48.diff
 
 -------------------------------------------------------------------
 Mon Jun 13 09:46:37 UTC 2016 - jengelh@inai.de

spirv-tools.spec

@@ -29,6 +29,7 @@ Url:            https://github.com/KhronosGroup/SPIRV-Tools
 
 Source:         %name-%version.tar.xz
 Patch1:         ver.diff
+Patch2:         gcc48.diff
 BuildRoot:      %{_tmppath}/%{name}-%{version}-build
 BuildRequires:  bison
 BuildRequires:  cmake >= 2.8.12
@@ -65,7 +66,7 @@ integration into other code bases directly.
 
 %prep
 %setup -q
-%patch -P 1 -p1
+%patch -P 1 -P 2 -p1
 
 %build
 %cmake -D"SPIRV-Headers_SOURCE_DIR=%_prefix"