[Mesa-dev] [PATCH 10/11] st/glsl_to_nir: Fix uninitialized access

[Tomeu Vizoso]

NIR_PASS will only set lower_flrp_progress if there's progress, and if
there isn't its value will be undefined.

Fixes this Valgrind error:

==6589== Conditional jump or move depends on uninitialised value(s)
==6589==    at 0x55CA7E6: st_nir_opts (st_glsl_to_nir.cpp:347)
==6589==    by 0x55CC1DD: st_nir_link_shaders(nir_shader**, nir_shader**, bool) (st_glsl_to_nir.cpp:667)
==6589==    by 0x55CCDAB: st_link_nir (st_glsl_to_nir.cpp:803)
==6589==    by 0x55C8C5F: st_link_shader (st_glsl_to_ir.cpp:167)
==6589==    by 0x5438B11: _mesa_glsl_link_shader (ir_to_mesa.cpp:3170)
==6589==    by 0x5371701: link_program (shaderapi.c:1216)
==6589==    by 0x5371701: link_program_error (shaderapi.c:1310)
==6589==    by 0x5372901: _mesa_LinkProgram (shaderapi.c:1802)
==6589==    by 0x509B459: shared_dispatch_stub_509 (glapi_mapi_tmp.h:21115)
==6589==    by 0x4799BF: glu::Program::link() (in /home/tomeu/deqp-build/modules/gles2/deqp-gles2)
==6589==    by 0x47A253: glu::ShaderProgram::init(glw::Functions const&, glu::ProgramSources const&) (in /home/tomeu/deqp-build/modules/gles2/deqp-gles2)

Signed-off-by: Tomeu Vizoso <tomeu.vizoso at collabora.com>
Fixes: d41cdef2a591 ("nir: Use the flrp lowering pass instead of nir_opt_algebraic")
Cc: Ian Romanick <ian.d.romanick at intel.com>
---
 src/mesa/state_tracker/st_glsl_to_nir.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/mesa/state_tracker/st_glsl_to_nir.cpp b/src/mesa/state_tracker/st_glsl_to_nir.cpp
index 0a67d4532eba..57064251313c 100644
--- a/src/mesa/state_tracker/st_glsl_to_nir.cpp
+++ b/src/mesa/state_tracker/st_glsl_to_nir.cpp
@@ -338,7 +338,7 @@ st_nir_opts(nir_shader *nir, bool scalar)
       NIR_PASS(progress, nir, nir_opt_constant_folding);
 
       if (lower_flrp != 0) {
-         bool lower_flrp_progress;
+         bool lower_flrp_progress = false;
 
          NIR_PASS(lower_flrp_progress, nir, nir_lower_flrp,
                   lower_flrp,
-- 
2.20.1